In order to study the contribution rate of built-in fin-type Trombe wall to reducing indoor heating energy consumption, taking ordinary residential houses in Lanzhou as the research object, fins are arranged on the heat absorption surface of Trombe wall to enhance heat transfer, so as to achieve the purpose of improving indoor thermal environment. The results show that the isosceles right-angled triangular fins with a height of 20 mm, a transverse spacing of 0.20 m, a longitudinal spacing of 0.533 m, and an in-line arrangement have the best improvement effect on the heat transfer performance of the Trombe wall and the thermal environment of the room. During the entire simulation period, the fin-type Trombe wall heat absorbing surface (Nu) ? is up to 21.28 higher than the finless Trombe wall heat absorbing surface (Nu) ?. Compared with the ordinary room, the energy saving rate of the finless Trombe wall room and the fin-type Trombe wall room is 36.38 % and 44.63 % respectively, that is, the energy saving rate of the fin-type Trombe wall room is 8.25 % higher than that of the finless Trombe wall room. This study has important theoretical reference value for promoting the process of clean energy utilization in solar-rich areas.