五功（阿拉伯语：أركان الإسلام‎，ʾarkān al-ʾIslām，即伊斯兰支柱）是伊斯兰教逊尼派所用的词汇，指信仰伊斯兰的所需遵守的五项基本原则。伊斯兰教的五功要求穆斯林“念、礼、斋、课、朝”，即“证信、礼拜、斋戒、天课和朝觐”。

通常在有生之年完成五功者，则可在其名前冠以“哈只”一词以表明身份。

The Five Pillars of Islam (arkān al-Islām أركان الإسلام; also arkān al-dīn أركان الدين "pillars of the religion") are five basic acts in Islam, considered mandatory by believers and are the foundation of Muslim life. They are summarized in the famous hadith of Gabriel.