An object of the present invention is to provide a more simplified and more efficient process for producing a highly purified orange roughy oil having high storage stability. The present invention provides a process for producing a highly purified orange roughy oil substantially free of a polyunsaturated fatty acid ester having 4 to 6 double bonds, and having a saponification value of 98 to 113 and an iodine value of 73 to 89, comprising washing with an alkaline aqueous solution to remove a free fatty acid; hydrogenating with a catalyst to reduce a polyunsaturated fatty acid ester; and purifying by treatment with an adsorbent.