<p> Background : Arteriovenous malformations (AVM) of brain are a rare cause of all hemorrhagic strokes with detection rate of approximately 1/100 000 person-years. But as AVMs affect more of young and healthy adults; they pose significant neurological problems for the community. Spetzler and Martin grading system was designed for prediction of the risk of morbidity and death from operative treatment , according to particular characteristics of a brain AVM. In this study we analysed Spetzler Martin grading as a predictor for surgical risk in patients of supratentorial cerebral arteriovenous malformations. Material methods : This was a prospective observational study conducted on consecutive patients of supratentorial cerebral arteriovenous malformations presenting at Bangur Institute of Neurosciences and IPGMER, Kolkata during study period from August 2011 to December 2013. A total 24 cases of supratentorial AVMs, diagnosed angiographically and fulfilling the said inclusion criteria were considered in the study. 7 patients underwent surgical procedure were analysed. Results: Out of 3 operated Spetzler and Martin Grade I patients 2 (66.6%) recovered with no neurodeficit, while one patient (33.3%) died. Out of 4 operated Spetzler and Martin Grade III patients 2 (55.0%) recovered with no neurodeficit, while 2 patients (50.0%) died. Conclusion : Spetzler Martin grading is good predictor of surgical risks in supra tentorial AVMs but Better patient selection utilizing supplementary grading system proposed by Lawton and colleagues, especially for Spetzler Martin grade III patients can further help in predicting the outcome.</p>