The meaning of spatial relations have been intensively studied in cognitive science research. A spatial template is one of the typical representations of spatial relations, which maps a position of a located object to its acceptability for the corresponding spatial term. Spatial templates have been investigated for several orthogonal spatial relations. However, diagonal spatial relations have attracted less attention. The present study aims at empirically determining the spatial template for a Japanese diagonal spatial term, "migiue (upper right)". The data was collected with various geometrical conditions changing the size of objects and the aspect ratio of the background. The analysis of the data revealed that the reference axis for "migiue (upper right)" was the direction of 45 degrees, and the acceptability of the diagonal relation could be affected by the acceptable regions of the adjacent orthogonal relations.