Rectiostoma thiobasis is a moth in the family Depressariidae.

The forewings are yellow suffused with pale green basally, concolorous, and continuous with the thorax and tegulae.

There are a few brown scales in the anal area and the distal margin of the yellow area is bordered by a dark brown line immediately paralleled by a broad, transverse band of iridescent blue violet.

The apical portion of the forewing is dark brown, irregularly patterned with iridescent blue violet.

The hindwings are dark brown with a white patch on the anterior margin.