Aim: To compare the success of slow rate with fast rate extracorporeal shock wave lithotripsy in the treatment of urolithiasis. Study design: Randomized controlled trial Place & duration of study: Department of Urology, Shaikh Zayed Hospital, Lahore from 1st October 2010 to 30th April 2011. Methodology: One hundredpatients who were divided in two equal groups i.e. Group A in which patients received treatment with slow rate extracorporeal shock wave lithotripsy and group B in which patients received treatment with fast rate extracorporeal shock wave lithotripsy. Results: The success rate of slow rate extracorporeal shock wave lithotripsy was 76 % and that of fast rate extracorporeal shock wave lithotripsy was 48% (p-<0.05). Conclusions: The slow rate extracorporeal shock wave lithotripsy is better than fast rate extracorporeal shock wave lithotripsy for elimination of urolithiasis. Keywords: Extracorporeal shock wave lithotripsy; slow rate ESWL; fast rate ESWL