To provide a leaving/entering control system with high reliability to prevent illegal leaving/enterance by pretending to be a baggage by a person who is not allowed to leave/enter a section.

A leaving/entering control system is provided with personal identification means (1, 3') to detect that a person to leave/enter a section is a person having freedaccess to the section and to output information to specify the person, a baggage weight measuring means (10) to measure weight of the baggage carried by the person to leave/enter the section, a total weight measuring means (7) to measure the total weight of the person to leave/enter the section and the baggage carried by the person and a second control part 8". Thus, the weight of the person to leave/enter the section is defined by subtracting the measured weight of the baggage from the measured total weight, and when an absolute difference between the weight and the weight which is stored corresponding to the person specified by the information is equal to or less than a prescribed value, the number of the persons to leave/enter the section is judged as one and when slight fluctuation of weighing is detected by the baggage weight measuring means, a weighed object is judged not as the baggage but as the person.