氯化铝，或三氯化铝，化学式为AlCl₃，是氯和铝的化合物。氯化铝熔点、沸点都很低，且会升华，为有离子性的共价化合物。熔化的氯化铝不易导电，和大多数含卤素离子的盐类（如氯化钠）不同。

AlCl₃采取“YCl₃”结构，为Al立方最密堆积层状结构， 而AlBr₃中Al却占Br最密堆积框架的相邻四面体间隙。熔融时AlCl₃生成可挥发的二聚体Al₂Cl₆，含有两个三中心四电子氯桥键，更高温度下Al₂Cl₆二聚体则离解生成平面三角形AlCl₃，与BF₃结构类似。

氯化铝是很常用的路易斯酸。在化学工业，它常是傅-克反应的催化剂。它亦用于烃的聚合和异构化反应中。

Aluminium chloride (AlCl₃) is the main compound of aluminium and chlorine. It is white, but samples are often contaminated with iron trichloride, giving it a yellow colour. The solid has a low melting and boiling point. It is mainly produced and consumed in the production of aluminium metal, but large amounts are also used in other areas of chemical industry. The compound is often cited as a Lewis acid. It is an example of an inorganic compound that "cracks" at mild temperature, reversibly changing from a polymer to a monomer.