The morphology of the excretory system of Hysterothylacium haze was examined by serial histological sections. The excretory system was H-shaped and glandular, consisting of lateral filaments and a commissure, with the exretory pore opening posterior to the nerve ring. A large excretory nucleus was present in the left filament. The cuticularized excretory duct was confined to the left side of the commissure. The glandular excretory system is rare among the Raphidascaridinae.