Syllepte microsema is a moth in the Crambidae family. It was described by Hampson in 1912. It is found in Sri Lanka, Singapore and Papua New Guinea. The wingspan is about 28 mm. The forewings are brown with a slight cupreous tinge. The antemedial line is indistinct, dark, oblique, from the costa to the median nervure, then more erect. There is a pale point in the middle of the cell and a slight whitish discoidal lunule both defined by dark-brown. The postmedial line is dark-brown, slightly incurved below the costa and oblique to vein 2, then retracted to below the end of the cell and excurved at vein 1. The hindwings are brown with a slight cupreous gloss and with a faint dark discoidal bar. The postmedial line is very indistinct, dark, slightly excurved between veins 5 and 2, then retract