When people move around in their environment, spatial updating, which is an automatic cognitive process, is essential to ensuring people can keep track of their relations between them and the surrounding objects, and to “recalculating” the relative position and orientation of those objects with regard to the current position of the persons. Despite the facilitating effect of spatial updating to people’s mental representation in most circumstances as demonstrated in most of the existing literature, the effect sometimes can be adversarial. For instance, some research suggested that even though people were asked to ignore their locomotion, it is difficult to suppress updating of the spatial representation during movement. The current two studies were conducted to systematically investigate the dual effects of spatial updating in both real and virtual environments. We used a typical spatial updating paradigm to explore the effects of scene familiarity (familiar vs. novel) and person’s locomotion (stationary vs. moving) on change detection accuracy (target object moved or not). The results indicated a facilitating effect of spatial updating in the novel scene condition, but an adversarial effect in the familiar scene condition-the dual effects, in both real and virtual environments. When people move around in their environment, spatial updating, which is an automatic cognitive process, is essential to ensure people can keep track of their relations between them and the surrounding objects, and to “recalculating” the relative position and orientation of those objects with regard to the current position of the persons. Despite the facilitating effect of spatial updating to people’s mental representation in most cases as demonstrated in most of the existing literature, the effect may can be adversarial. For instance, some research suggests that even though people were asked to ignore their locomotion, it is difficult to suppress to of systematically investigate the dual representation of the spatial reproduction in both real and virtual environments. We used a typical spatial updating paradigm to explore the effects of scene familiarity (familiar vs. novel) and person’s lo The results indicate a facilitating effect of spatial updating in the novel scene condition, but an adversarial effect in the familiar scene condition-the dual effects, in both real and virtual environments.