Vibration is the most considerable factor in dynamics of machinery. Vibration causes unfavorable effects on engine components and may reduce the life of engine. The conventional fossil fuel sources are limited in the world. The dependency on diesel should be reduced by using biodiesel as an alternative fuel in next few years. The input parameters are affected on engine performance and emission. The present study mainly focuses on an optimization of vibrations, performance and emission using Taguchi and multiple regression analysis for biodiesel as a fuel. The test was performed on single cylinder, four-stroke, diesel engine with VCR. Taguchi method is used to prepare the design of experiment of L16 array for minimizing number of experiments and multiple regression analysis for finding the best relationship between the input and output parameters. The selected input parameters are: fuel fraction, compression ratio, injection pressure and injection timing. Simarouba biodiesel with different blends of 0%, 10%, 20% and 30% are used as fuel with diesel for experimentation at full load of 12 kg. From experimentation the optimum input parameters obtained are: 20% fuel fraction, 18 compression ratio, 250 bar injection pressure and 23o bTDC injection timing. The optimized condition has given better performance with lower vibrations and emission. Index Terms: VCR, Fuel fraction, compression ratio, injection pressure, injection timing, Simarouba Biodiesel, Taguchi method, multiple regression analysis.