Background: Today opium dependence is widely prevalent in certain states of India, especially Rajasthan, Punjab, Haryana, Madhya Pradesh (MP) etc. In rural areas of western Rajasthan crude opium is consumed with a social acceptance by a notable proportion (8.0%) of adult male population. Later on they become addicted to it. Objective: to observe the changes in liver function parameters in opium addicted subjects in Jodhpur division of Western Rajasthan. Methods: The present study was conducted in Department of Physiology of Dr. S. N. Medical College, Jodhpur. Total three hundred (300) adult male subjects with age ranged from 25 to 45 years were participated in this study. Among them 150 were opium addicted and were considered as study group (Group B) and another 150 apparently healthy adult male of same age group were designated as control group (Group A). Opium addicts were consuming about 5–11 gm/day opium for >2 years. Then liver function tests were evaluated by estimating total plasma protein, albumin, globulin, serum aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase, serum bilirubin and fasting blood sugar of both the groups. Results: In this study AST, ALT and alkaline phosphatase levels were found highly significantly (p<.01) higher in group B as compared to those of group A. Again, there were significantly (p<.01) higher increase in serum bilirubin, blood glucose level and albumin in group B as compared to those of group A. while total protein and globulin was decrease significantly in group B as compared to those of group A. Conclusion: It is concluded that chronic long term use of opium, increases the risk of hepatic and results in various infectious disease.