The Gourami fish as a source of animal protein is a type of freshwater fish that has a high nutritional content. One of the problems faced in gourami hatchery activities is the low survival rate. In overcoming the low survival of gourami fish, the solution that can be done is to improve cultivation environmental factors and stocking density. This study is to analyze changes in blood glucose and oxygen consumption of gourami fish fry (Osphronemus gouramy) reared at various densities. This study used a completely randomized design (CRD) with 4 treatments, each consisting of 3 replicates. The different density treatments tested were stocking density A (4 fish/L), B (6 fish /L), C (8 fish /L) and D (10 fish /L). The gourami used were 7 cm in size as many as 250 fish, with a maintenance period of 15 days. The test parameters in this study include blood glucose and oxygen consumption. To test the blood glucose level of gourami fish, it is measured using an enzymatic method (glucose oxidase peroxidase) in a centrifuge with a wavelength of 635 nm and oxygen consumption measurements are made using a device called a DO meter or analytically by titration (idiometric method, winkler). The results indicated that the highest stocking density of 8 fish/L resulted in a blood glucose level of 8.28 mg/dL, which significantly affected the glucose levels (P < 0.05). In addition, this density results in the lowest oxygen consumption rate of 5.51 mg/L. These findings suggest that optimizing the stocking density can improve the physiological health, highlighting the importance of environmental factors in aquaculture.