Microserica mutabilis is a species of beetle of the family Scarabaeidae. It is found in Indonesia (Java).
Adults reach a length of about 3.5 mm. They have a shortly rounded, dull, black (although the head is somewhat greenish), faintly opalescent body. They are silky-glossy underneath. The pronotum is almost straight laterally, not projecting anteriorly. The elytra are irregularly punctate in the striae, with the intervals only slightly raised, but still clearly visible.