通过对理论计算、腐蚀称重、碳含量测定等方法的比较，研究了ＳｉＣｐ／Ａｌ复合材料孔隙度的测定方法。结果表明，采用理论计算法来表征复合材料的孔隙度很不准确，腐蚀称重法虽然精确但比较繁琐，碳含量测定存在较大的误差。提出了一种新的方法—车屑法，并用此方法研究了复合材料搅拌时间和孔隙度的关系，表明孔隙度随搅拌时间的上升而增加。 Through the comparison of theoretical calculation, corrosion weighing, determination of carbon content and other methods, the determination of porosity of SiCp / Al composites was studied. The results show that it is inaccurate to calculate the porosity of the composite material by theoretical calculation method. Although the corrosion weighing method is accurate but cumbersome, there is a big error in the determination of carbon content. A new method, chip turning method, was proposed and the relationship between the mixing time and porosity of the composites was studied. The results show that the porosity increases with the stirring time.