Vegetable oils are basically of fatty acids and the amount present can affect the properties of the resulting biodiesel. The aim of this study is to investigate how the transesterification affects the fatty acid profile of the resulting biodiesel produced. Seven vegetable oil types were selected for the study. They were transesterified and blended with diesel and the fatty acid profiles determined by method of gas chromatography. The results obtained shows that fatty acid profile of vegetable oils changes slightly after transesterification and mostly constant with blending.