Objective       To analyze the biochemical stone compositions of urinary calculi and investigate the distribution in general population of Guizhou province.       Methods       Clinical data of 708 patients with identified urinary calculi living in Guizhou province admitted in the provincial hospital from December 2009 to September 2012 were retrospectively collected. Infrared spectrophotometry was carried out for biochemical composition analysis of urinary stones retrieved by endoscopic

open surgery

or spontaneously or by extracorporeal shock wave lithotripsy. Gender

age and stone location among these patients were evaluated

and the results were analyzed with biochemical stone analysis.       Results      Urinary calculi were most common in the patients at the age of 40 to 60

and with an incidence of male to female of 1.97∶1. The most dominant composition of urinary stones was calcium oxalate (94.77%)

followed by carbonate apatite (38.70%)

uric acid or ammonium urate (13.42%)

ammonium magnesium phosphate (3.53%)

calcium hydrophosphate (0.56%)

and cystine (0.28%).       Conclusion      The dominant stone composition in inhabitants of Guizhou province is calcium oxalate

which significantly higher than other regions of China. Some special measures should be taken to prevent urolithiasis in Guizhou province.