Hydrogenation of CO2 to formic acid (FA) is a promising method to meet the increasing energy demand and reduce CO2 emissions. In this work, efficient catalyst was successfully designed and synthesized by loading uniformly dispersed Ir nanoparticles on N- or S-doped carbon materials, catalyzing the hydrogenation of CO2 to FA. The experimental results showed that the catalytic performance of N-doped Ir/NC catalyst was much higher than that of S-doped Ir/SN catalyst. Ir/NC catalyst exhibited a high catalytic performance under the reaction conditions of 120℃, 8 h and 6 MPa with a turnover number (TON) of 987. Moreover, a high TON of 3901 was achieved after 48h, thus indicating the good stability of the obtained catalyst.