Abstract: A medical simulator includes: a luminal organ model having flexibility and having a shape that simulates at least one luminal organ, the luminal organ model including a constricted wall portion having a lumen cross-sectional area smaller than the lumen cross-sectional area of a periphery of the constricted wall portion, the constricted wall portion being provided in a first specific region including a portion corresponding to one end portion of one luminal organ or corresponding to a joining portion of two luminal organs; a first space formation portion that circumferentially covers at least an outer periphery of the first specific region of the luminal organ model to form a first sealed space at the outer periphery of the first specific region; and a fluid controller that controls a fluid pressure of a to-be-controlled fluid within the first sealed space to expand or contract the lumen cross-sectional area of the constricted wall portion of the luminal organ model.