本文简单地介绍了空气中低浓度α,β放射性微尘测量的一般方法,其中对α测量着重在介绍如何消除天然放射性的影响,而对β测量则着重在介绍如何消除现场γ影响的问题。同时,介绍了用能量分析法来测量低浓度长半寿期的α放射性污染。适当地选择工作条件,可以减少天然放射性对测量的影响。估计当天然放射性浓度为10~(-12)居里/立升时,仪器的灵敏度为10_(-14)—10~(-15)居里/立升。 This article briefly introduces the general methods of measuring low-level radioactive dust particles in the air. The measurement of α focuses on how to eliminate the effects of natural radioactivity. The measurement of β focuses on how to eliminate the effects of γ on the spot. At the same time, we introduced the energy analysis method to measure α radioactive contamination with low concentration and long half life. Appropriate choice of working conditions, can reduce the impact of natural radioactivity on the measurement. Estimated when the natural radioactive concentration of 10 ~ (-12) Curie / 立 升, the sensitivity of the instrument 10 _ (- 14) -10 ~ (-15) Curie / 立 升.