Objective: To compare the outcome of percutaneous ultrasound guided aspiration V/S open surgical drainage for psoas muscle abscess. Methodology: This comparative study was conducted in department of general surgery at Liaquat medical university hospital Hyderabad/Jamshoro, from June 2017 to November 2017. Diagnosed Patients of psoas muscle abscess size more than 5cm, between 18 to 60 years of age and either of gender were included. Patients were randomly divided into two groups, A and B by odd and even method, patients in group A abscess was aspirated by percutaneous ultrasound guided aspiration and patients in group B was underwent open surgical drainage, all the data were entered in the pre designed performa and analyzed into SPSS V:16.0 Results: A total of 58 patients of Psoas muscle abscess were selected, the mean age of study subjects of group A was 38.5+10.5 and group B was 36.5+12.7 (p-673). Early post-operative pain relief was assessed among patients of group A as compared to group B. As per outcome resolution of abscess cavity was significantly high among patients of group B (p-0.004), while post-operative Hospital stay was significantly lower in group A (p-0.002). Conclusion: Both techniques has their own benefits like percutaneous aspiration has shorter duration of hospital stay while in complete resolution of abscess cavity was found in open surgical drainage group of patients.