Medicinal plants are considered more accessible, affordable and also associated with minimal side effects compared to orthodox medicines in most developing countries. These factors in addition to multiple cultural and long term historical relevance have contributed to its increasing popularity around the world. This study was carried out to assess the antioxidative and serum lipid effects of leaf extract of Rhizophora mangle on male Wistar rats. Male Wistar rats were divided into four (4) groups of five (5) rats each. Group one (1) served as control and received distilled water. Group two (2) and group three (3) were treated with 200mg/kg bw and 400mg/kg bw of the ethanolic extract of Rhizophora mangle respectively. Group four (4) was treated with 600mg/kg of the extract. Extract administration lasted for 30 days. The results obtained showed that the extract did not cause significant changes in superoxide dismutase, catalase, gluthathione reductase enzyme activities but decreased gluthathione peroxidase enzyme activity. The level of malondialdehyde was not altered. The lipid parameters including low density lipoprotein cholesterol, high density lipoprotein cholesterol, triglyceride and total cholesterol concentrations were not significantly affected. This study showed that, extracts of Rhizophora mangle did not alter the level of lipid peroxidation and may not confer any benefits against development of lipid induced-cardiovascular disorders.