The invention provides a SDN controller location selection method, which is characterized by comprising the following steps: I, calculating a time delay matrix; II, calculating a pseudo neighborhood of nodes; III, judging whether a control network meets reliability or not, if the control network meets reliability, executing a step IV, otherwise, executing a step V; IV, joining in the nearest node in the pseudo neighborhood; V, obtaining a neighborhood matrix; VI, calculating minimum covering; VII, obtaining a SDN controller location corresponding to the minimum covering. In the method provided by the invention, a controller location selection scheme is solved through a method based on the minimum covering, time delay requirement between a switch and the controller is satisfied, and average amount of the switches losing controller connection when being affected by single link failure is reduced, reliability of the control network is relatively high, moreover, the location selection method provided by the invention has steady and efficient effects in networks of different scales and different connectivity.