Objectives Research suggests that content of delusion and hallucination in schizophrenia is influenced by culture and social environment. However, few studies investigated chronological change of delusions and hallucinations within a society. To investigate changes in delusions and hallucinations of schizophrenia according to time, we compared contents of symptoms between inpatients with schizophrenia at two different time frames. Methods All admissions to a psychiatric unit of Hanyang University Guri Hospital with discharge diagnoses of schizophrenia at two different five-year time frames (1996-2000 and 2006-2010) were reviewed. Using a checklist, adapted from the Scale for Assessment of Positive Symptoms, we investigated delusions and hallucinations of 247 patients (104 in the 1990s and 143 in the 2000s). Results Delusions and hallucinations of patients did not differ at two time frames. In women, however, auditory and somato-tactile hallucinations were significantly more frequent in the 1990s (p < 0.05). Conclusions Our findings support the literature emphasizing that content and frequency of hallucination may differ according to cultural environment. We speculate that attitude toward sex and defensiveness toward disclosure of symptoms may have contributed to interval difference.