To efficiently organize an event (convention) and to appropriately provide information on the event.

A convention organization support system 1 is provided with a storage part 3 for storing an event table setting the contents and reception limit of the convention and a participant table for registering the information of participants in the convention determined by the event table. Further, this system is provided with a reception means for acquiring the information of participants in the convention determined by the event table through a network 6 and adding this participant information to the event table while adding participant ID for individually specifying the participant information when the reception time of the participant information is within the said reception limit.