In order to study the effects of biomass oxygen-containing fuel on diesel engine performance and combustion characteristics at high-altitude anoxic environment, atmosphere simulation device was used to simulate atmospheric pressure at high-altitude environment. The performance test of high-pressure common rail diesel engine fueled with pure diesel B0 (0# diesel), B20 and B50 was carried out at simulated altitude of 2 000 m (atmospheric pressure 81 kPa). The test results show that the incylinder combustion pressure, heat release rate and cylinder temperature peak of B20 and B50 decrease, and they reach the peak at the crank angle advanced by 1°CA to 2°CA at 1 200 r/min. The three parameters of B20 present a downward trend at 2 200 r/min. The cylinder pressure and heat release rate of B50 basically present a downward trend, but they are higher than those of pure diesel at 60% load of 2 200 r/min with 5% and 2.6% increase respectively. The cylinder temperature of B50 also has a maximum increase of 4%. In addition, the equivalent fuel consumption rate increases and the thermal efficiency decreases for B20 and B50 fuel.