Abstract: The essential difference between the thermal environment on the lunar surface and that in the earth-orbit is the influence of lunar infrared heat flow. The analysis of the lunar topographical characteristics is the basis for determination of the infrared influence of the lunar surface. Four kinds of typical lunar landforms are selected in the lunar maria, together with the corresponding thermo-physical parameters. Conclusions are drawn through calculation and analysis on the effects of the lunar landforms on the thermal control systems of lunar landing vehicles. It is shown that flat lunar surfaces and slopes have the largest influence; the influence of rocks and small craters can be ignored while large craters behave similar to the slopes.