Abstract: This study was conducted to test the immunostimulatory effect of graded dose of alanine supplementation on inactivated vaccine immunized mice. Animals were randomly divided into five groups: mice were immunized with inactivated vaccines, mice were treated with dietary 0.5% alanine supplementation and immunized with inactivated vaccines, mice were treated with dietary 1.0% alanine supplementation and immunized with inactivated vaccines, mice were treated with dietary 2.0% alanine supplementation and immunized with inactivated vaccines and all the mice immunized with PBS. Results found that alanine supplementation has little significant effect on serum antibody production, serum interleukin-1 beta and 8 levels and survival rate of mice after challenge. However, higher dose of alanine supplementation increased serum GSH-PX activity compared to the lower dose of alanine supplementation. Collectively, dietary alanine supplementation has little effect on the immune parameters in vaccine immunized mice indicating alanine can be used as isonitrogenous control to study the immune regulatory function of other amino acids.