The synthesis and characterization of a series of hole transporting materials (HTMs) based on carbazole core and dimethoxytriphenylamine (WA) groups are reported. By modifying the number of WA components in the HTMs, the influence of the structure of HTMs molecules on the photovoltaic performance of CH3NH3PbI3 perovskite solar cells are investigated. TPA(2)C, in which two TPA units are incorporated onto the carbazole core, exhibited higher photovoltaic performance than TPA(1)C, TPA(3)C and TPA(4)C, which contain one, three and four TPAs, respectively. The introduction of WA group from one to two can improve the device result, however, additional branches introduced to the carbazole core did not led to higher efficiency.