Background: Polycystic ovary syndrome (PCOS) is a common disorder in women of reproductive age closely related to insulin resistance, obesity, dyslipidaemia and long term diseases including diabetes and cardiovascular disease. The management of PCOS may be challenging on account of the comorbidities associated with the disease. Objective: The objective of the study was to evaluate the effect of Levocarnitine supplementation on physical and biochemical parameters in polycystic ovary syndrome. Methods: This randomized controlled study was conducted in the Department of Reproductive Endocrinology and Infertility, Bangabandhu Sheikh Mujib Medical University, Dhaka from January 2021 to December 2021. Total 78 diagnosed cases of PCOS were selected for medication and were included in this study. Eligible women who gave their informed consent were allocated into either Group A (Levocarnitine) or Group B (Placebo) on the basis of computer generated table. Group A received Levocarnitine and Group B received Placebo for 12 weeks. Then pretreatment and post treatment physical parameters including BMI, waist circumference and biochemical parameters including cholesterol, triglyceride, LDL, HDL, fasting plasma glucose, fasting insulin, HOMA-IR were assessed. Results: Treatment with levocarnitine significantly reduced BMI (-6.00±0.00 vs -0.45±0.07) waist circumference (-4.88±2.85 vs -0.77±0.30) compared with the placebo. In Levocarnitine group, total cholesterol (-38.15±7.33 vs -0.79±27.00 mg/dl), serum triglycerides (-60.00±53.33 vs. -0.33±9.59 mg/d) and LDL (-23.49±1.81 vs. -0.41±0.07 mg/dl) were significantly reduced and HDL level was significantly increased (4.23±1.62 vs 0.41±0.49 mg/dl) compared with the placebo group. Moreover, compared with the placebo, levocarnitine led to a significant reduction of fasting plasma glucose, fasting insulin and HOMA-IR (-0.49±0.95 vs. 0.09± 0.29). Conclusion: In conclusion, levocarnitine administration led to an improvement in physical parameters including BMI, waist circumference as well as biochemical factors including cholesterol, triglyceride, LDL, HDL. Insulin resistance was significantly reduced in post treatment patients of Levocarnitine. In contrast, although physical and biochemical parameters improved in the placebo group, the change was not significant.