In this paper, the station apartment is transformed into the sunspaces-attaching passive solar house in the Inner Mongolia region. Through the calculation of dynamic simulation software, we evaluate and analyze the result of the simulation, as well as the economic calculation of the attached sunspace. Through the analysis found that the sunspaces-attaching passive solar house only need 15.93 W/m 2 to meet heating demand. The results show the building for attached sunspace is completely feasible in the solar-rich northern region.