The road transportation sector has been the greatest consumer of gasoline in the country. Continuously growing demand of the sector has caused serious challenges the most important of which has been the gasoline supply problem. The deficit caused by difference between import price and sales price of gasoline has always put pressure on the government’s budget. As the first step, to solve this problem, gasoline consumption was supplied by quota since July 2007 using smart cards. Unlike most studies which studied this policy from an economical point of view, using data mining techniques, this paper has a new approach. Two-step clustering is used for this purpose. Data are gathered from 2005 to 2010 for the city of Tehran. Since the period contains years before and after gasoline quota, the study results seem satisfactory to conclude about the gasoline quota effects. The results show that the policy had a short-term impact on the reduction of gasoline. Moreover taxi trips was a short term solution and that expansion of Metro lines is a long term solution to solve the road transportation sector dilemma.