The decline in efficiency and the frequent toxicity effects observed with antibiotics urge researchers to investigate medicinal plant-based therapies. This study aimed to evaluate the anti-salmonella activity of the methanol extract of Harungana madagascariensis, a plant commonly used in Cameroon by traditional healers. Thirty Wistar albinos male were divided into six groups (normal control, negative control, positive control and three test groups). Test groups received the plant extract at 75, 150 and 300 mg/kg body weight (b.w). The disease evolution and treatment effectiveness were monitored by feces culture from the second-day post-infection until the end of the treatment. In addition, the effects of treatment on growth performances and feed conversion efficiency of rats were evaluated. The extract significantly affected the number of viable Salmonella typhimurium recovered from feces and could stop salmonellosis after 12 days of treatment. The hematological parameters were assessed after infection and treatment. The biological parameter and some serum and tissue oxidative stress markers were also evaluated. Moreover, the plant extract increased the weight of infected rats and normalized levels of TCMH (3.06; 2.83 and 3.16 Pg), CCMH (30.00; 26.66 and 20.00 g/dL) and lymphocytes (3.20; 3.20 and 3.10 μL). The results indicate that the extract of Harungana madagascariensis could be potentially used in salmonellosis treatment.