Salmonella infections remain one of the major health problems in both poultry farming and human medicine. In addition, resistance to Salmonella has emerged as a global health problem in both sectors. The present study aimed at evaluating the in vivo antisalmonellal and antioxidant activities of 95° ethanol extract of Khaya grandifoliola using broiler chickens as animal model. Animals were divided into the normal control group, negative control group, positive control group and three test groups treated with the extract at 10, 20 and 40 mg/kg respectively. The antioxidant status of broiler chickens was also evaluated by measuring the concentration of enzymatic antioxidants (catalase, glutathione peroxidase) and biochemical markers (malondialdehyde and nitric oxide). The results showed that infected animals treated with the Khaya grandifoliola extract at 40 mg/kg recovered on day 11 after the beginning of the treatment and on day 13 for those treated at the 10 and 20 mg/kg. The antioxidant assay showed that the infection led to the reduction of enzymatic markers in the body of infected animals, while the treatment increases such makers. The infection resulted in a significant increase in serum and pulmonary malondialdehyde. It also caused a significant decrease in cardiac and pulmonary nitric oxide whereas the treatment depending on the doses of the extract tends to normalize these biochemical markers. The overall results showed that Khaya grandifoliola extract can be successfully used in the treatment of avian salmonellosis as well as the management of the oxidative stress caused by the infection.