The rapid development of technology in the 4.0 era has led to an increasing demand for energy. One step to overcome this energy problem is through the use of bioethanol. Bioethanol is an alternative energy source that can be obtained from plant materials, one of which is molasses. In this study, bioethanol was used as a mixture for Pertalite type fuel to evaluate engine performance such as power and torque as well as exhaust emissions in the form of CO, HC, and CO2. The tests were carried out at variation levels of PB0, PB10, PB20, PB30, and PB40 using engine speeds ranging from 2000 to 7000 rpm. The results of the study show that increasing bioethanol improves effective power and torque in mixtures with a proportion of 20% at rpm variations. The maximum effective power was recorded at 7.0 Hp at 5000 rpm, while the torque showed an increase of 13.97 Nm at 3000 rpm. Meanwhile, exhaust emissions such as CO, HC, and CO2 showed a decrease. The CO level decreased by 0.16%, the HC level by 58 ppm, and the CO2 level by 10.2%, which occurred at PB40 under idle rpm conditions.