Most of interior spaces are the places for social interaction, it is expected that they considers better interpersonal relationships and behaviors. The main aim was to examine whether physical factors of interior space under normal conditions affects impression formation. White-collar workers, one hundred fifty six in the Experiment 1, three hundreds sixty four in the Experiment 2, estimated interpersonal impression and expectation in interpersonal relationship by looking at photomontages of an adult man combined with CGs of interior space. Next they evaluated physical factors, such as spaciousness, brightness and view, and pleasantness and liking, by looking at CGs. The results of path analysis for the Experiment 1 and 2 indicated that the structure, spaciousness affect communality of person perception and then communality affect expectation of interpersonal relationship, is a model has high fit indices. These results suggest that physical factors of interior spaces affect impression formation.