Pachyserica jianfengensis is a species of beetle of the family Scarabaeidae. It is found in China (Hainan).
Adults reach a length of about 8.1 mm. They have a dark reddish brown, ovoid body. The frons, pronotum, scutellum and impunctate portions on the elytra with a rather strong greenish sheen, while the abdomen is strongly iridescent. The legs are reddish brown and the antennae are yellowish brown.
The species name is derived from its type locality, Jianfengling.