Gastroserica haoyui is a species of beetle of the family Scarabaeidae. It is found in China (Zhejiang).
Adults reach a length of about 7.2 mm. They have a dark brown, oval body. The legs, antennae, labroclypeus, midline and lateral margins of the pronotum and a moderately wide longitudinal stripe on the elytra are all yellowish brown. The dorsal surface is moderately shiny, with moderately dense, long, erect setae.
The species is named after its collector, Liu Haoyu.