Abstract: From centuries human has been afflicted by urinary calculi (Urolithiasis). These calculi are formed from crystal aggregation and retention in the urinary tract. The incidence and prevalence of urolithiasis may be related to various factors including age, sex, ethnicity, diet, fluid intake, genetic predisposition, climatic conditions, and urinary tract infections. Study of chemical composition and ultrastructure of various types of calculi helps in understanding mechanism of urolith nucleation, growth and aggregation; subsequently, it helps in prevention and management of urolithiasis. In the present investigation, PXRD technique was used to determine mineral composition of renal calculi. Results of the present investigation revealed that renal calculus of calcium oxalate is more abundant than calcium salts of phosphate. Among the calcium salts of oxalate, whewellite form is more abundant than weddellite form.