The detailed formation mechanism of increased number of haze events in China is still not very clear. Here, we found that reduced surface visibility and an increase in satellite derived columnar concentration of inorganic precursor concentrations are connected with each other. Typically higher inorganic mass fractions lead to increased aerosol water uptake and light scattering ability in elevated relative humidity. Satellite observation of aerosol precursors of NO 2 and SO 2 showed increased concentrations during study period. Our in-situ measurement of aerosol chemical composition in Beijing also confirmed increased contribution of inorganic aerosol fraction as a function of increased particle pollution level. Our investigations demonstrate that the increased inorganic fraction in the aerosol particles is a key component in the frequently occurring haze days during studying period, and particularly the reduction of nitrate, sulfate and their precursor gases would contribute towards better air quality in China.