This study performed factor analysis for 21 independent variables related to the effect of illumination and suggested the effect by multiple regression analysis on the relationship between the effect of illumination and the satisfaction of use of a dependent variable to find the effect of illumination in urban parks at night and the effect of illumination on the satisfaction of use. The results of this study are as follows; 1) Of the 21 independent variables used to study the effect of illumination in urban parks at night, the impact on safety and possibility of crime was highly. The effects of illumination by factor analysis were abstracted as effects of removing anxiety, securing safety, increasing use. 2) As a result of multiple regression analysis, independent variables influencing satisfaction of use in urban park were proved as effects of removing anxiety, securing safety, increasing identity, preparing atmosphere and increasing use. Also, the effect of securing safety was the most important factor; it showed a level of importance 2 times higher than the effect of removing anxiety, and 7.7 times higher than the effect of preparing atmosphere in relative contribution of the effect of illumination to satisfaction of use. 3) Of the effects of illumination influencing satisfaction of use in urban parks, the effect of securing safety and the effect of increasing visibility were more significant than the effects of removing anxiety, preparing atmosphere and increasing use. This fact means that personal safety an the identity of persons or facilities in the space of use should be considered with priority in planning or designing illumination. Also, it implies hat, for night use in urban parks, lightness of the space is required for general safety of use at parks, and proper illuminance on the activity in the space of use should be required. The subject parks of this study are 8 urban neighborhood parks. The model on the effect of illumination and the satisfaction of use depends on characteristics and conditions of location of he park and user class, so the subject parks and persons should be varied, and the difference by sex or ages should be suggested.