Gastroserica loei is a species of beetle of the family Scarabaeidae. It is found in Thailand.
Adults reach a length of about 4.5âÂÂ5.4 mm. They have a yellowish brown, oval body. The antennal club, frons and margins of the elytra are blackish and the dorsal surface is shiny and nearly glabrous.
The species is named after its occurrence in the Loei province.