Biodiesel is an alternative, environment-friendly, and renewable fuel type for diesel engines; and its importance is increasing with each passing day. Many studies have been conducted on biodiesel and it has been suggested to be used in the engine directly. Two engines with the same characteristics have been used in this study. The respective engine wear rates are compared by running one of the engines with 100% biodiesel (B100) fuel and the other with petroleum diesel under the same operating conditions. The wear rates are determined by being analyzed in an inductively coupled plasma spectrometer. At the end of the research, it was seen that biodiesel reduced the wear for some engine parts and increased wear for some others due to oil acids and oxidation.