Depression is caused as a multifactorial psychiatric disorder and the reasons associated are genes, environmental, psychological, and biological factors. There are several molecular changes in the pathogenesis of depression. Antioxidants in the body like catalase was found to be deranged in patients suffering from depression. The present observational cases-control study was carried out in the Physiology Department of Rural Medical College Loni in collaboration with Psychiatry department. Total 183 subjects recruited for study. Out of total subjects 83 patients were diagnosed with depression and 100 were normal individuals without any psychiatric disorder. A non-probabilistic international sampling method was adopted for the selection of subjects. Significant decrease in serum catalase was observed in patient suffering from depression as compared to normal healthy individuals (p value < 0.05).The present study finds decreased serum catalase levels in patient suffering from depression as compared to the normal healthy controls.