To provide a method for deodorizing a liquid unsaturated ester wax which is an oil of an orange roughy (Hoplosterbus altanticus) or an oil of a dory (a fish of Allocyttus sp. or Pseudocyttus maculatus) that is a natural resource, consisting essentially of a long-chain unsaturated liquid ester wax and containing an extremely readily oxidizable highly unsaturated acid and its glyceride as impurities due to the emission of a strong malodor.

This ester wax is deodorized by using a nickel-aluminum alloy and an alkali metallic hydroxide in combination suitable as a catalyst capable of selectively initiating the hydrogenation only for contained various highly unsaturated acids or their glycerides. Since the neutralization of the highly unsaturated acids, saponification of the glycerides and steam distillation by heat are simultaneously carried out according to the method, extremely excellent deodorizing effects are obtained. When a degumming treatment, a deacidifying treatment, a washing treatment with hot water, a filtering treatment and a heat treatment are added thereto in the method, a much higher level of the deodorization is achieved.