In Riptortus clavatus, photoperiodic sensitivity persisted and diapause was re-induced in response to short-day conditions after prompt termination of adult diapause under long-day conditions. After gradual diapause termination under short-day conditions in the laboratory, some adults regained the photoperiodic sensitivity and went into a second diapause under short-day conditions. After diapause termination in the field in Kyoto, most adults became sensitive to a diapause-inducing photoperiod. Nevertheless, a second diapause in the field seems improbable in this region, because overwintering adults kept under quasi-natural conditions died before diapause re-induction.