Cyperispa thoracostachyi is a species of beetle of the family Chrysomelidae. It is found on the Solomon Islands.
Adults reach a length of about 5.2-6 mm. Adults are pale castaneous, with the antenna pitchy in the middle, but pale on last two segments. There is broad black band on the elytra.
The recorded food plants are Arecaceae, Thoracastachyum and Pandanus species.