The cardioprotective effects of Persea americana extract was investigated on biochemical activities of high salt-fed adult Wistar rats in this study.Forty healthy Wistar rats of both sexes weighing 120 to 150 g were randomly assigned into 8 groups of 5 rats each (groups A, B, C, D, E, F, G, and H). Rats in groups A, F, G, and H were fed with standard laboratory pellets, while groups B, C, D, and E were fed on the high-salt diet for 4 weeks. Concomitantly, daily administration of 50, 100, and 150 mg/kg of the P americana extract were given orally to groups C and F, D and G, and E and H, respectively, while rats in groups A and B were administered distilled water. Blood samples were taken by cardiac puncture; concentration of sodium ion, potassium ion, nitric oxide, and activity of lactate dehydrogenase were determined. One-way analysis of variance was used to analyze data, followed by Student-Newman-Keuls (SNK) test for multiple comparison.Results revealed that concentration of potassium ion and nitric oxide was significantly lower ( P < .05) in high salt-fed groups. Sodium ion concentration and activity of lactate dehydrogenase were higher in high salt-fed group while P americana prevented biochemical perturbations in other experimental groups.In conclusion, high salt-diet induced biochemical alterations which were significantly protected by oral administration of P americana extract.