The invention discloses a steam drain mechanism for dish washers, comprising an outer cover with at least one steam outlet, and an inner cover for a steam condensing channel and detachable from the inner cover. With the invention, the steam with moisture is retained in the condensing channel for a longer time to improve condensing efficiencies, as a result, the problem that the air becomes moistened due to the operation of the dish washers is avoided, enabling to provide and keep continuous and comfortable indoor environment.