Separation of EPA and DHA from fish oil fatty acid ethyl ester (FAFE) by urea adductive crystallization method was carried out in the supercritical carbon dioxide (SC $CO_2$) as a solvent. Our results showed that SC $CO_2$ is a good candidate as a solvent in the urea adductive crystallization to separate FAFE by the number of unsaturated bonds. Compared to the separation process using methanol. SC $CO_2$ yielded better performance in the overall selectivity of EPA and DHA. The effect of process variables on separation of EPA and DHA was discussed in detailed. A hybrid technology of SC $CO_2$ fractionation and urea adductive crystallization with SC $CO_2$ was conformed as a viable process to separate and concentrate EPA and DHA from fish oil.