Treatment-emergent obsessive-compulsive symptoms (OCSs) have raised concern since the widespread introduction of serotonin-dopamine antagonists (SDAs) for the treatment of schizophrenia. Further investigations of SDA-emergent OCSs and their response to anti-obsessional agents will be beneficial for clinicians in helping patients who suffer from this problem. We present three cases of schizophrenia in which distressing OCSs occurred during clozapine or risperidone treatment. OCSs were assessed consecutively using the Yale-Brown Obsessive-Compulsive Scale. The OCSs of these three patients were responsive to anti-obsessional agents, including fluvoxamine, clomipramine, and paroxetine. We also review the current literature and discuss the possible pathophysiology and psychopathology of SDA-emergent OCSs.