Abstract: Male sterility plays an important role in the hybrid breeding of water dropwort (Oenanthe javanica (Blume) DC.). In the current study, a male-sterile water dropwort (OJBY001) with a degenerated stamen was described. OJBY001 was characterized by many lateral branches, dark green leaf blades and petioles, atrophic filaments and anthers, elongated stigma, and the ability to secrete nectar and receive exotic pollen from other water dropwort belonging to O. javanica. Compared to fertile water dropwort (OJKY002), OJBY001 exhibited significantly higher stem and petiole dry matter and and significantly or extremely significantly higher contents of vitamin C, soluble sugar, and flavonoids in the stolon.