Serotonin (5-hydroxytryptamine; 5-HT) is a neurotransmitter that occupies a uniquely important place in neurobiology because of its role in many physiologic processes such as sleep, appetite, thermoregulation, pain perception, hormone secretion, and sexual behavior. Serotonin dysfunction has been implicated in the pathogenesis of schizophrenia. Previous studies have shown an association between the T102C polymorphism of the 5-hydroxytryptamine receptor 2A (HTR2A) gene and schizophrenia. However, many negative findings have also been reported. We analyzed the T102C polymorphism of HTR2A of schizophrenic patients in two southern Chinese populations (n = 291) and matched controls (n = 307). No significant positive association was observed between either of the polymorphisms and all schizophrenics, nor was the polymorphisms and any population of schizophrenia. These data did not provide evidence for a contribution of the 102T/C SNP of HTR2A gene to susceptibility to the southern Han Chinese schizophrenia.