Micrairoideae is a subfamily of the grass family Poaceae, distributed in tropical and subtropical regions.

[1] Within the PACMAD clade, it is sister to subfamily Arundinoideae.

A phylogenetic classification of the grasses recognises four main lineages, classified as tribes.

Only species in tribe Eriachneae (genera Eriachne and Pheidochloa) have evolved the C4 photosynthetic pathway.

[3] Relationships of tribes in the Micrairoideae according to a 2017 phylogenetic classification,[4] also showing the Arundinoideae as sister group: Arundinoideae Micraireae Eriachneae Isachneae