This study was contributed to supplement the data on morphology, and the flexibility of morphometric and meristic measurement of the mudskipper Periophthalmodon septemradiatus, a potential aquarium pet in the Mekong Delta. A total of 1,504 individuals (930 males and 574 females) were collected from August 2017 to July 2018 at five sites in Hau River, from An Giang to Soc Trang. The analysis result of 1,504 individual showed that the total length (TL) and the body weight (W) of this species varied with gender and site, but not season. The variations of TL and W of males and females depended on season but not site. The interaction of site and season influenced on the change of TL and W. External color of males varied with the environmental condition at different sites. The morphometric and meristic parameters of this mudskipper displayed a spatial variation based on the data analysis of 150 individuals (93 males and 57 females). The results supplied additional knowledge for fish identification and understanding the ecological adaptation of this fish in the study regions.