Single particle mass spectrometry has been widely used to determine the size and chemical compositions of atmospheric aerosols; however, it is still rarely used for the microphysical properties measurement. In this study, two methods were developed for determining aerosol effective density by a single particle aerosol mass spectrometer(SPAMS). Method I retrieved effective density through comparison between measured light scattering intensities and Mie theoretical modelled partial scattering cross section. Method II coupled a differential mobility analyzer(DMA) with SPAMS to simultaneously determine the electric mobility and vacuum aerodynamic diameter, and thus the effective density. Polystyrene latex spheres, ammonium sulfate and sodium nitrate were tested by these methods to help validate their effectiveness for determining the aerosol effective density. This study effectively extends SPAMS measurements to include particle size, chemical composition, light scattering, and effective density, and thus helps us better understand the environment and climate effects of aerosols. Single particle mass spectrometry has been widely used to determine the size and chemical compositions of atmospheric aerosols; however, it is still rarely used for the microphysical properties measurement. In this study, two methods were developed for determining aerosol effective density by a single particle aerosol Method II 结果 I 回收 模式 (SPAMS). Method I 回收 有效 密度 通过 间接 间 测量 光 散射 强度 和 M theoretical 理论 模型 partial scattering cross section. Method II coupled a differential mobility analyzer (DMA) with SPAMS to simultaneously determine the electric mobility and vacuum aerodynamic diameter, and thus the effective density. Polystyrene latex spheres, ammonium sulfate and sodium nitrate were tested by these methods to help validate their effectiveness for determining the aerosol effective density. This study valid extends SPAMS measurements to include particle size, chemical composition, light scattering, and effective d ensity, and thus helps us better understand the environment and climate effects of aerosols.