Abstract: The performance of two multisphere coupled climate system models developed by the Beijing Climate Center (BCC_CSM) to simulate the annual modes of tropical precipitation is evaluated and possible reasons for the resulting simulation biases are discussed. The results indicate that both BCC_CSM1.1 and BCC_CSM1.1(m) can reasonably reproduce the major characteristics of the global annual mean precipitation and annual modes of tropical precipitation. The solstice modes simulated by the two models exhibit equatorial antisymmetric structure, which corresponds to observations. BCC_CSM can reasonably reproduce the relationship between the spring-fall asymmetric mode and tropical sea surface temperature (SST). The biases in air temperature, atmospheric circulation, and tropical SST contribute to the deficiency of the solstice modes. The simulation biases in the SST annual cycle contribute to the biases in the spring-fall asymmetric mode of tropical precipitation. The differences in horizontal resolution of atmospheric model and land model affect the simulation of precipitation annual modes in BCC_CSM to some extent. The comparison shows that the spatial variabilities of climatological monthly precipitation from January to December simulated by BCC_CSM1.1 (m) are closer to the observations than those by BCC_CSM1.1 and the SST annual cycles in the tropical ocean are generally more reasonable in BCC_CSM1.1 (m) owing to its finer horizontal resolution. However, obvious biases remain in BCC_CSM1.1 (m). Therefore, further work is required to improve the performance of BCC_CSM.