Rice comes second after wheat in Iran`s food consumption economy. Rising population and recent growth in GDP has made Iran one of the greatest rice importer countries all over the world. That is why rice marketing has always been a controversial issue in Iran`s agricultural economics. To study rice marketing system in Iran, this paper aims to calculate rice marketing margin, market efficiency and marketing cost coefficient in seaside Mazandaran province( where 70 percent of domestic rice production is obtained )Over the period 2000-2010. Results show that firstly HYV`s wholesale marketing margin is less than local varieties in 2000 while this trend is reversed in 2010. Secondly, retail marketing margin, total marketing margin, market efficiency and cost marketing coefficient for local varieties are all greater than HYV. Consequently, agricultural cooperative`s encouragement would lead to decrease in rice marketing margin and role of traders and raises rice farmers earnings