Abstract: Carp is widely sold and used in its fresh in Iran, however, recently a range of value additions may also be observed. It is essential to the sustainable development of a carp farm to know the production costs and their contribution. Warm-water fish farming is mainly based on common, silver, grass and bighead carp and the common carp and the three Chinese species are often reared in poly culture in Iran. Since, the 1970S carp farming has spread around the Caspian coast and farmed production reached a peak in 2006 with production of more than 73,400 tons. A study of production, costs and profitability of carp farming sector was carried out to help clarify carp production costs and their difference with location in 2001. A total of 101 farms from the three main carp farming provinces, Guilan, Mazandaran and Khuzestan were randomly selected, classified and studied. The results of the survey showed that the various producer provinces have different cost structures. Overall, feed and fertilizer with the highest level of variation accounted for 23% of total costs, followed by seed and labor and salary with 23 and 17%, respectively. On average, benefit-cost ratio and the rate of farm income were closely related to location. This result suggests that farmers practice more efficiently and have better conditions in Mazandaran, followed by Guilan province.