diff --git a/language/predefined/attributes.xml b/language/predefined/attributes.xml
index 49734b6c453..eaced5e7bf1 100644
--- a/language/predefined/attributes.xml
+++ b/language/predefined/attributes.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- $Revision$ -->
-<!-- EN-Revision: fe11910e25e7eba44959bd347ba946ffc4d56934 Maintainer: mumumu Status: ready -->
+<!-- EN-Revision: e890e4a7f97a9ea85e60a38443e7c8eb7ae9383f Maintainer: mumumu Status: ready -->
 <part xml:id="reserved.attributes" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
  <title>定義済みのアトリビュート</title>
 
@@ -12,6 +12,7 @@
 
  &language.predefined.attributes.attribute;
  &language.predefined.attributes.allowdynamicproperties;
+ &language.predefined.attributes.deprecated;
  &language.predefined.attributes.override;
  &language.predefined.attributes.returntypewillchange;
  &language.predefined.attributes.sensitiveparameter;
diff --git a/language/predefined/attributes/deprecated.xml b/language/predefined/attributes/deprecated.xml
new file mode 100644
index 00000000000..ff1bab94e86
--- /dev/null
+++ b/language/predefined/attributes/deprecated.xml
@@ -0,0 +1,141 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- $Revision$ -->
+<!-- EN-Revision: e890e4a7f97a9ea85e60a38443e7c8eb7ae9383f Maintainer: KentarouTakeda Status: ready -->
+<!-- CREDITS: KentarouTakeda -->
+<reference xml:id="class.deprecated" role="class" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xi="http://www.w3.org/2001/XInclude">
+ <title>Deprecated クラス</title>
+ <titleabbrev>Deprecated</titleabbrev>
+
+ <partintro>
+
+  <section xml:id="deprecated.intro">
+   &reftitle.intro;
+   <simpara>
+    このアトリビュートは、機能を非推奨としてマークします。
+    マークされた機能を使用すると、<constant>E_USER_DEPRECATED</constant> エラーが発生します。
+   </simpara>
+  </section>
+
+  <section xml:id="deprecated.synopsis">
+   &reftitle.classsynopsis;
+
+   <classsynopsis class="class">
+    <ooclass>
+     <modifier>final</modifier>
+     <classname>Deprecated</classname>
+    </ooclass>
+
+    <classsynopsisinfo role="comment">&Properties;</classsynopsisinfo>
+    <fieldsynopsis>
+     <modifier>public</modifier>
+     <modifier>readonly</modifier>
+     <type class="union"><type>string</type><type>null</type></type>
+     <varname linkend="deprecated.props.message">message</varname>
+    </fieldsynopsis>
+    <fieldsynopsis>
+     <modifier>public</modifier>
+     <modifier>readonly</modifier>
+     <type class="union"><type>string</type><type>null</type></type>
+     <varname linkend="deprecated.props.since">since</varname>
+    </fieldsynopsis>
+
+    <classsynopsisinfo role="comment">&Methods;</classsynopsisinfo>
+    <xi:include xpointer="xmlns(db=http://docbook.org/ns/docbook) xpointer(id('class.deprecated')/db:refentry/db:refsect1[@role='description']/descendant::db:constructorsynopsis[@role='Deprecated'])">
+     <xi:fallback/>
+    </xi:include>
+   </classsynopsis>
+  </section>
+
+  <section xml:id="deprecated.props">
+   &reftitle.properties;
+   <variablelist>
+    <varlistentry xml:id="deprecated.props.message">
+     <term><varname>message</varname></term>
+     <listitem>
+      <para>
+       非推奨となった理由と可能なら代替機能を説明する追加のメッセージ。
+       発生する非推奨エラーのメッセージに含まれます。
+      </para>
+     </listitem>
+    </varlistentry>
+    <varlistentry xml:id="deprecated.props.since">
+     <term><varname>since</varname></term>
+     <listitem>
+       <para>
+        機能がいつから非推奨になったかを示す追加の文字列。
+        内容は PHP によって検証されず、バージョン番号、日付、
+        または適切と考えられる他の値を含むことができます。
+        発生する非推奨エラーのメッセージに含まれます。
+       </para>
+       <para>
+        PHP 自体の機能は、<varname>since</varname> の値として Major.Minor を利用します。
+        例えば <literal>'8.4'</literal> です。
+       </para>
+     </listitem>
+    </varlistentry>
+   </variablelist>
+  </section>
+
+  <section>
+   &reftitle.examples;
+   <informalexample>
+    <programlisting role="php">
+<![CDATA[
+<?php
+
+#[\Deprecated(message: "use safe_replacement() instead", since: "1.5")]
+function unsafe_function()
+{
+   echo "This is unsafe", PHP_EOL;
+}
+
+unsafe_function();
+
+?>
+]]>
+    </programlisting>
+    &example.outputs.84.similar;
+    <screen>
+<![CDATA[
+Deprecated: Function unsafe_function() is deprecated since 1.5, use safe_replacement() instead in example.php on line 9
+This is unsafe
+]]>
+    </screen>
+   </informalexample>
+  </section>
+
+  <section xml:id="deprecated.seealso">
+   &reftitle.seealso;
+   <simplelist>
+    <member><link linkend="language.attributes">アトリビュートの概要</link></member>
+    <member><methodname>ReflectionFunctionAbstract::isDeprecated</methodname></member>
+    <member><methodname>ReflectionClassConstant::isDeprecated</methodname></member>
+    <member><constant>E_USER_DEPRECATED</constant></member>
+   </simplelist>
+  </section>
+
+ </partintro>
+
+ &language.predefined.attributes.deprecated.construct;
+
+</reference>
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+indent-tabs-mode:nil
+sgml-parent-document:nil
+sgml-default-dtd-file:"~/.phpdoc/manual.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:nil
+sgml-local-ecat-files:nil
+End:
+vim600: syn=xml fen fdm=syntax fdl=2 si
+vim: et tw=78 syn=sgml
+vi: ts=1 sw=1
+-->
diff --git a/language/predefined/attributes/deprecated/construct.xml b/language/predefined/attributes/deprecated/construct.xml
new file mode 100644
index 00000000000..52cd1b61d7c
--- /dev/null
+++ b/language/predefined/attributes/deprecated/construct.xml
@@ -0,0 +1,64 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- $Revision$ -->
+<!-- EN-Revision: e890e4a7f97a9ea85e60a38443e7c8eb7ae9383f Maintainer: KentarouTakeda Status: ready -->
+<!-- CREDITS: KentarouTakeda -->
+<refentry xml:id="deprecated.construct" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
+ <refnamediv>
+  <refname>Deprecated::__construct</refname>
+  <refpurpose>新しい Deprecated のインスタンスを作成する</refpurpose>
+ </refnamediv>
+
+ <refsect1 role="description">
+  &reftitle.description;
+  <constructorsynopsis role="Deprecated">
+   <modifier>public</modifier> <methodname>Deprecated::__construct</methodname>
+   <methodparam choice="opt"><type class="union"><type>string</type><type>null</type></type><parameter>message</parameter><initializer>&null;</initializer></methodparam>
+   <methodparam choice="opt"><type class="union"><type>string</type><type>null</type></type><parameter>since</parameter><initializer>&null;</initializer></methodparam>
+  </constructorsynopsis>
+  <simpara>
+   新しい <classname>Deprecated</classname> のインスタンスを作成します。
+  </simpara>
+ </refsect1>
+
+ <refsect1 role="parameters">
+  &reftitle.parameters;
+  <variablelist>
+   <varlistentry>
+    <term><parameter>message</parameter></term>
+    <listitem>
+     <para>
+      <property linkend="deprecated.props.message">message</property> プロパティの値。
+     </para>
+    </listitem>
+   </varlistentry>
+   <varlistentry>
+    <term><parameter>since</parameter></term>
+    <listitem>
+     <para>
+      <property linkend="deprecated.props.since">since</property> プロパティの値。
+     </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+ </refsect1>
+</refentry>
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+indent-tabs-mode:nil
+sgml-parent-document:nil
+sgml-default-dtd-file:"~/.phpdoc/manual.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:nil
+sgml-local-ecat-files:nil
+End:
+vim600: syn=xml fen fdm=syntax fdl=2 si
+vim: et tw=78 syn=sgml
+vi: ts=1 sw=1
+-->
diff --git a/reference/reflection/reflectionclassconstant/isdeprecated.xml b/reference/reflection/reflectionclassconstant/isdeprecated.xml
new file mode 100644
index 00000000000..e098150c5d1
--- /dev/null
+++ b/reference/reflection/reflectionclassconstant/isdeprecated.xml
@@ -0,0 +1,92 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- $Revision$ -->
+<!-- EN-Revision: 7de265dc47277aaf9b3c9f29d9691364aa0350ca Maintainer: KentarouTakeda Status: ready -->
+<!-- CREDITS: KentarouTakeda -->
+<refentry xml:id="reflectionclassconstant.isdeprecated" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
+ <refnamediv>
+  <refname>ReflectionClassConstant::isDeprecated</refname>
+  <refpurpose>クラス定数が非推奨かどうかを調べる</refpurpose>
+ </refnamediv>
+
+ <refsect1 role="description">
+  &reftitle.description;
+  <methodsynopsis role="ReflectionClassConstant">
+   <modifier>public</modifier> <type>bool</type><methodname>ReflectionClassConstant::isDeprecated</methodname>
+   <void/>
+  </methodsynopsis>
+  <simpara>
+   クラス定数が非推奨かどうかを調べます。
+  </simpara>
+
+ </refsect1>
+
+ <refsect1 role="parameters">
+  &reftitle.parameters;
+  &no.function.parameters;
+ </refsect1>
+
+ <refsect1 role="returnvalues">
+  &reftitle.returnvalues;
+  <simpara>
+   クラス定数が非推奨なら &true; を、そうでなければ &false; を返します。
+  </simpara>
+ </refsect1>
+
+ <refsect1 role="examples">
+  &reftitle.examples;
+  <example>
+   <title>
+    <methodname>ReflectionClassConstant::isDeprecated</methodname> の例
+   </title>
+   <programlisting role="php">
+<![CDATA[
+<?php
+class Basket {
+    #[\Deprecated(message: 'use Basket::APPLE instead')]
+    public const APLE = 'apple';
+
+    public const APPLE = 'apple';
+}
+$classConstant = new ReflectionClassConstant('Basket', 'APLE');
+var_dump($classConstant->isDeprecated());
+?>
+]]>
+   </programlisting>
+   &example.outputs;
+   <screen>
+<![CDATA[
+bool(true)
+]]>
+   </screen>
+  </example>
+ </refsect1>
+
+ <refsect1 role="seealso">
+  &reftitle.seealso;
+  <simplelist>
+   <member><classname>Deprecated</classname></member>
+   <member><methodname>ReflectionClassConstant::getDocComment</methodname></member>
+  </simplelist>
+ </refsect1>
+
+</refentry>
+<!-- Keep this comment at the end of the file
+Local variables:
+mode: sgml
+sgml-omittag:t
+sgml-shorttag:t
+sgml-minimize-attributes:nil
+sgml-always-quote-attributes:t
+sgml-indent-step:1
+sgml-indent-data:t
+indent-tabs-mode:nil
+sgml-parent-document:nil
+sgml-default-dtd-file:"~/.phpdoc/manual.ced"
+sgml-exposed-tags:nil
+sgml-local-catalogs:nil
+sgml-local-ecat-files:nil
+End:
+vim600: syn=xml fen fdm=syntax fdl=2 si
+vim: et tw=78 syn=sgml
+vi: ts=1 sw=1
+-->