Abstract: In utilization of biomass, it is very important for an exact determination of ash characteristics. However, there are no specific standards for biomass-ash analysis in China. The standards for coal-ash analysis are usually used to determine the property of ash in biomass. For a better understanding to the effects of different analysis methods on the results, 8 biomasses including wood dust, cornstalk, corn cob, rice shell, soybean stem, cotton stem, bark and leaf, were ashed at low temperature (corresponding to the temperature required in the standard of ASTM/E 870-82, amended in 1998) and at high temperature (corresponding to the temperature required in the standard of GB/T212－2001). The contents of ash were measured and the composition and morphology of the ash were analyzed using EDX-SEM. The results reveal that ashing temperature has a remarkable effect on the ash content, composition and morphology. Thus it is better to use low temperature ashing method for an exact determination of ash property. A proposal that the standards of biomass quality analysis should be established as soon as possible in China is put forward.