Disclosed are a method and a device for determining the position of a virtual object in a virtual space. The method comprises: detecting whether a predetermined triggering condition is met; when the predetermined triggering condition is met, acquiring at least three sampling points by sampling a movement trajectory of a peripheral device in a reality space; when the movement trajectory forms a loop, determining a reality space plane on which the sampling points exist; converting the reality space plane into a target plane in the virtual space according to a preset transformation relation; and determining the position of a virtual object in the virtual space by setting a designated side of the virtual object on the target plane. By the method and the device according to the present invention, the position of a virtual object in a virtual space may be determined according to the position of a reality object in a reality space, thereby determining the position of the virtual object in the virtual space.