Abstract: The ultrastructure of the reproductive system for male and female Dermatophagoides farinae (Hughes) was observed with transmission electron microscopy (TEM). The male reproductive system of D. farinae consists of testis, vasa deferentia, accessory gland, ejaculatory duct, copulatory organ and accessory copulatory organs. All stages of spermatogenesis exist simultaneously in the testis. A typical sperm is characterized by short of nucleus, chromosomal material in threads, mitochondria without typical cristae, and cytoplasm with conspicuous parallel electron-dense lamellae. The female reproductive system consists of copulatory bursa, ductus bursae, receptaculum seminis, ducti receptaculi, ovaries, oviducts, chorion glands, and the ovipositor. The ovary contains a large multinucleated central cell surrounded by oocytes and other germ cells. The results broaden our understanding of the reproductive system of D. farinae.

Key words: Dermatophagoides farinae, reproductive system, testis, ovary, ultrastructure, transmission electron microscopy (TEM)