The ovarian development, spawning pattern and season, size at first maturity and fecundity of Glossogobius sparsipapillus, which is an essential commercial fish in the Mekong Delta, have been studied. Totally, 317 fish were collected from the estuarine and the coastal regions including Vinh Hau, Hoa Binh to Dien Hai, Dong Hai (Bac Lieu Province) and Tan Thuan, Dam Doi (Ca Mau Province). Fishes were sampled using gill nets during the dry and wet seasons in April 2019 – January 2020. The results show that the ovaries have different types of oocytes and that this goby was a multiple spawner. It spawned from July to September at three of the studied sites, since most of the mature ovaries appeared at that time. The size at first maturity (Lm) was from 6.50 cm in Vinh Hau and Tan Thuan to 6.78 cm in Dien Hai. The average batch fecundity was 24,966±2,542 eggs, ranging from 17,918±2,258 SE in Vinh Hau to 28,700±5,322 SE in Dien Hai, followed closely by Tan Thuan (26,352±3,458 SE).There was an increase in batch fecundity with fish size. The fish total length and weight had strong positive relationships with batch fecundity. The egg size was 48.20±4.89 SE µm length and 26.39±3.09 SE µm width.