This study evaluated brake specific fuel consumption and regulated emissions from palm biodiesel fuel (palm BDF) used on diesel generators. The tests were performed at an idle and high load with different mixing rate blends between diesel fuel and palm BDF (0 %, 5 %, 10 %, 15 %, 20 %, 50 %, 100 % which was called B0, B5, B10, B15, B20, B50 and B100) respectively. The results showed at each loading mode, brake specific fuel consumption increased when the volume of palm BDF rose in the blends. At the idle mode, brake specific fuel consumption increased 1.32 %, 1.8 %, 2.8 %, 3.74 %, 5.61 %, 6.54 % for B5, B10, B15, B20, B50, B100, compared with B0. Similarly at the high load mode, brake specific fuel consumption improved 1.51 %, 1.86 %, 2.18 %, 4.78 %, 5.36 %, 6.76 % for B5, B10, B15, B20, B50, B100, compared with B0. In both two load modes, when the volume of palm BDF in the fuel blends grew gradually, the concentration of CO, SO2 and CxHy emission reduced while the concentration of NO and NO2, CO2 went up. Emission factors of CO, SO2 and CO2 at high load are higher than those at an idle load, regardless the ratio of palm BDF to diesel fue. Conversely, emission factors of NO, NO2 at high load are higher.