Pachyserica horishana is a species of beetle of the family Scarabaeidae. It is found in Taiwan.
Adults reach a length of about 10.1 mm. They have a dark brown, oval body. The elytral stripes and legs are reddish-brown and the antennae are yellowish-brown. The surface is almost entirely tomentose except for the labroclypeus and the upper surface has white scale-like hairs. The elytra are without erect setae.