In urban areas people want to have various activities in nighttime as well as in daytime. But there're few researches on nighttime townscapes or comfortableness compared with daytime ones. In this paper we try to clarify some factors of enviromental evaluation of nighttime public space. As a result of a psychological experiment of amenity evaluation by the same way of the daytime one we've made in 1986, we got 4 factors of improving and detracting amenity, and pointed out charactors of nighttime evaluation compared with daytime one. Based on those results we arranged effective space design ways as to 6 types of urban public space.