This study aimed to analyze the economic feasibility of Mackerel offshore aquaculture production performance in Jeju region, Korea. Based on the collected biological, costs and market price data, farming revenue and expenses during the farming period were evaluated, and the net present value and the internal rate of return of a 10-year cash inflow and cash outflow were estimated to determine the economic feasibility of Mackerel offshore aquaculture production system. Model results indicated that the Mackerel offshore aquaculture production performance would have high profitability under the current production and market situation. This is because of the relatively high survival rate, relatively low feed conversion ratio and good market prices. However, sensitivity analyses of main important biological and economic variables showed that the economic viability of Mackerel offshore aquaculture production system would be highly vulnerable to production and market condition changes.