The objectives is to compare the effect of haloperidol and olanzapine on physical parameters and also to observe the adverse effects of both the drugs in schizophrenic patients. A prospective observational follow up study was conducted for 18 months by enrolling 121 patients of  the age group 18 to 65 from psychiatry clinic. It was found that in both the groups there were more number of male (52.25%) patients and 44.14% patients is from the age group of 18 to 29 yrs.  At 12th week Olanzapine treated group shows statistically significant (p=<0.03) gain in body weight and on comparison the groups shows marginal association between weight gain and olanzapine intake at 8th and 12th  week. There were no significant difference in systolic and diastolic BP in both the groups at 8th and 12th week.