Around the globe there is demand for the development of a bio-based lubricant which is biodegradable, nontoxic, and environmentally friendly. This paper outlines the friction and wear characteristics of Mongongo biodiesel contaminated bio-lubricant by using pin-on-disc tribometer. To formulate the bio-lubricants, Mongongo-oil (MO)-based biodiesel was blended in the ratios 5%, 8%, and 12% by volume with the base lubricant SAE 20W 40. Tribological characteristics of these blends were carried out at 3.8 m/s sliding velocity, and loads applied were 50, 100, 150 N. Experimental results showed that the lubrication regime that occurred during the test was boundary lubrication, while the main wear mechanism was the adhesive wear. During testing, the lowest wear was found with the addition of 5% and 8% MO-based biodiesel, and above this contamination, the wear rate was increased considerably. The addition of 5% (MO 5) and 8% (MO 8) MO-based biodiesel with the base lubricant acted as a very good lubricant additive which reduced the friction and wear rate during the test. It has been concluded that the MO 5 and MO 8 can act as an alternative lubricant to increase the mechanical efficiency at 3.8 m/s sliding velocity and contribute in reduction of dependence on the petroleum-based products.