Tris(8-hydroxyquinolinato)aluminium is the chemical compound with the formula Al(C9H6NO)3.

Widely abbreviated Alq3, it is a coordination complex wherein aluminium is bonded in a bidentate manner to the conjugate base of three 8-hydroxyquinoline ligands.

Both the meridional and facial isomers are known as well as several polymorphs (different crystalline forms).

[1] The compound is prepared by the reaction of 8-hydroxyquinoline with aluminium(III) sources[4] Alq3 is a common component of organic light-emitting diodes (OLEDs).

Variations in the substituents on the quinoline rings affect its luminescence properties.