Background: Urolithiasis is one of the common conditions in the society and it needs medical attention due to its increase in prevalence. The use of the homeopathic medicines has found to be,of great importance in the treatment of urolithiasis and certainly homoeopathy is a promising eld in this condition. Objectives: The aim of this study was to evaluate the mechanism of urolithiasis and the inhibitory action of homeopathic drug Tribulus terrestris by in vitro experiment. Materials and Method: Homoeopathic preparation of Tribulus terrestris Q, 6C, 12C, 30C, 200C, 1M was planned to evaluate in vitro calcium oxalate and calcium phosphate crystallization using spectro-photometric and colorimetric assay respectively. Considering the role of reactive oxygen species as one of the etiological factors in stone formation, effective antioxidant activity of Tribulus terrestris was also performed by 2,2- diphenyl -1-picrylhydrazyl (DPPH) free radical scavenging assay. Result: Tribulus terrestris Q, 200C and 1M exerted maximum inhibition as 33.62%, 23.89% and 23.00% respectively to calcium oxalate nucleation assay whereas, Tribulus terrestris Q, 6C, 12C, 30C, 200C, 1M exerted maximum inhibition to calcium oxalate aggregation assay up to 76.19%. Tribulus terrestris 12C and 30C showed maximum inhibition as 82.28% and 16. 21% to calcium and phosphate ions respectively. Presence of antioxidant activity by DPPH radical assay for Tribulus terrestris Q and 12C which showed percentage inhibition as 33.11% and 0.95% respectively. Conclusions:Homoeopathic preparation Tribulus terrestris has potential effect on inhibition of calcium oxalate and calcium phosphate crystallization and also homoeopathic preparation of Tribulus terrestris is capable of showing presence of phytochemicals; anti-oxidant activity when performed by in vitro experiment.