介绍新国标GB/T 4 2 4 9《公差原则》中“最小实体要求”的基本内容和应用方法。对被测要素、基准要素在应用“最小实体要求”时 ,尺寸公差与形位公差相互补偿问题进行计算分析。从所举例子可看出 ,零件加工中采用“最小实体要求”是能够大大提高产品的合格率的 Introduce the basic content and application method of “the minimum entity requirement” in the new national standard GB / T 4 2 4 9 “tolerance principle”. For the measured elements, the benchmark elements in the application of the “minimum entity requirements”, dimensional tolerances and geometric tolerances mutual compensation problems were calculated and analyzed. As can be seen from the examples, the use of “minimum physical requirements” in parts processing is able to greatly improve the passing rate of the product