The egg, second, third, fourth and adult stages of Hysterothylacium haze (Nematoda : Anisakidae) obtained from Japanese common goby, Acanthogobius flavimanus, were described using light and scanning electron microscopy. The major dimensions and dimension indexes were given in association with body length and developmental stages. The dimensions were thought to be influenced by maturation and moulting. The characteristic features of each stage were also given.