Æ, æ（古英语：æsc，现代英语：ash，发音为 [æʃ]）是丹麦语、挪威语、冰岛语、法罗语的一个字母。这个字母在以前的英语和法语中也有使用。

在英语和法语，æ 多用在一些从拉丁语中借来的外来词，如法语的 et cætera、tænia、ex æquo 和英语的 archæology、encyclopædia、nebulæ、athenæum 等。在现代英语中，多由ae或e所取代，如 archaeology 或 encyclopedia，但仍有专有名词的孤例保留，如《大英百科全书》（Encyclopædia Britannica）。

Æ (minuscule: æ) is a grapheme named æsc or ash, formed from the letters a and e, originally a ligature representing a Latin diphthong. It has been promoted to the full status of a letter in the alphabets of some languages, including Norwegian, Danish, Icelandic, and Faroese. As a letter of the Old English Latin alphabet, it was called æsc ("ash tree") after the Anglo-Saxon futhorc rune ᚫ () which it transliterated; its traditional name in English is still ash /æʃ/. It was also used in Old Swedish before being changed to ä. Variants include Ǣ ǣ Ǽ ǽ.