Pachyserica tianxuani is a species of beetle of the family Scarabaeidae. It is found in China (Chongqing).
Adults reach a length of about 9.7 mm. They have an oblong-oval and convex body. The body (including antennae and legs) is reddish brown, the elytra with dark, green spots. The dorsal surface is dull, partly with a weak iridescent shine, while the frons and pronotum have dark green toment and long, erect, yellow setae. The entire body has dense, white, scale-like setae, the elytra also with some longer and erect setae.
The species is named after the collector of the holotype, Mr. Tian-Xuan Gu.