Abstract: We study the cognitive rules of people choosing routes in large stores by using online questionnaires, finding that people at different gender, ages, educational background can make the same decision when they are faced with the choice of the stair or route to go upstairs or downstairs. People have obvious tendency when they go upstairs but do not have obvious tendency when they go downstairs. Most people will choose the escalator when the floor span is below or equal to two. However, most people will choose the elevator when the floor span is more than two. These rules are quite valuable for the analysis of the optimal path when the two points in indoor space are on different floors.