Soil organic matter ( SOM) was determined by heating method with an aluminum module digesting device, instead of the conventional oil-bath heating. The optimal digestion conditions for SOM analysis were digesting temperature of 220℃ ( Boil-ing in digestion tube, potassium dichromate solution was about 170℃) , and boiling time of 12 min ( digestion time of 22 mi-nutes) , by which SOM content had small deviation in the standard values of soils, with oxidizing rate and coefficient of SOM of 99. 98% and 1. 00, respectively. Moreover, the standard deviation (SD) and coefficient of variance (CV) of SOM content in chinese typical soils determined by the heating method with the aluminum module digesting device ranged from 0. 06~0. 78 and 0. 30% ~4. 11%, respectively, indicating meeting the requirements of the laboratory for SOM analysis. Compared with the con-ventional oil bath heating, the method developed in this study was easier to operate, safer and simpler, and lower pollution cre-ated, along with higher accuracy and precision, so it is promising in batch analysis of SOM content.%铝模块消解仪加热法替代油浴加热消解土壤样品,测定土壤中有机质含量。通过优化消解仪的消解温度、加热时间等实验,确定消解仪温度220℃(沸腾时消化管内溶液温度约为170℃),沸腾时间12 min (消解时间约为22 min)为铝模块消解仪的最佳有机质测定条件。使用该方法测定的土壤标准样品的有机质含量均在误差允许范围以内,消解样品有机质回收率达99．98%,校正系数为1．00。同时用我国长期定位试验典型土壤进行该方法准确度和精密度测试,样品有机质测定结果标准偏差为0．06~0．78,变异系数为0．30%~4．11%,符合测定要求。与经典油浴加热方法相比,该方法温度易控制、操作简单、安全,可降低环境污染；结果的准确度和精密度满足要求,值得推广。
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