The invention provides a fan sharing control method. The fan sharing control method includes the steps that a random ID is automatically generated for each server; the IDs of the servers are transmitted and received among the N servers, and the IDs of the N servers are stored in an ID comparison table; according to a preset rule and the ID comparison table, one of the N servers is selected as a control server; the control server acquires the revolutions per minute of fans required by the N servers and controls the revolutions per minute of the fans of a sharing fan set according to the revolutions per minute of the fans required by the N servers. The invention further provides a fan sharing control system. According to the system and method, additional hardware consumption is not needed, cost is saved, and the number of the servers of sharing the fans does not need to be limited.