Marine and coastal ecosystems have many benefits and different services for humans that marine aquaculture is one of the most important of these services. Southern coast of Caspian Sea particularly Mazandaran coast have great potential for development of marine aquaculture. Now, there are 9 fish farms with different production capacities in Mazandaran coast. In this study, the growth of specie of fish Rainbow trout (Oncorhynchus mykiss) was modeled using the marine aquaculture model based on daily temperature, rate of metabolism and mortality rate. Finally calculated the harvest weight and net present value (Net Present Value: NPV) for this this specie in each farm was calculated by considering two scenarios: 1) Development and 2) BAU (Business as Usual) that in each scenario equal to 2786 and 1121 tons with the NPV 11158 and 15788 million toman in total mazandaran coast during 1 years. So production of Rainbow trout is more economic. Results show that growth cycle fom the release (200 g) to harvest for Rainbow trout and is 2 cycle in 1 year. Also, duration of growth cycle decreases when temperature increases such that at 14, 16 and 18 degrees Celsius was142, 124 and 110 days, respectively. Since aquaculture farms on the Mazandaran coast had been grownd mostly Rainbow trout so this study is evaluated the production and NPV for this specie. Rainbow trout is a non-native specie in South Caspianso so is necessary that be studied effects and consequences of production the specie in this area.