In this study, a new scheme for the radiative transfer algorithm, called the two-four stream spherical harmonic expansion approximation, is built and applied in the new version of the Beijing Climate Center atmospheric general circulation model (BCC_AGCM2.0.1). It is then compared with the original Eddington approximation scheme. Because this new scheme expands the Eddington approximation to solve radiative transfer through the atmosphere, it has better accuracy. We found the new scheme to have a great effect on climatic simulation. In a clear sky, the new scheme reduces the shortwave downward radiative flux in the surface in the 30°-60°S regions, in the Northeast Atlantic, and in the Sahara desert, with the largest reduction being 3.5 W/m². Meanwhile, it increases the shortwave upward radiative flux at the top of the atmosphere (TOA) in the 30-60°S regions and in the Northeast Atlantic, with the largest increase being 3 W/m². For all-sky cases, the new scheme reduces the shortwave downward radiative flux, and the difference between the two schemes becomes larger with increasing latitude. The largest difference reaches 5.5 W/m² in the two polar regions. The new scheme also reduces the shortwave upward radiative flux at the TOA in the tropics, with the largest difference being 2.5 W/m², but increases this flux in the 30°-60°S regions, with the largest difference being 1.5 W/m². Moreover, the new scheme increases the shortwave heating rate within the atmosphere generally, especially for the levels between 800 hPa and the surface and between 50 and 100 hPa where the largest difference reaches 0.03 K/d. Therefore, the new scheme is useful in global climate modeling for improving the so-called temperature cold bias phenomena generally existing in the lower parts of the stratosphere above the tropics.