This developmental study explores the effect of oblique orientation on spatial perspective taking (SPT) in children between 5 and 9 years old. SPT is the ability to represent how an object or array of objects looks from another viewpoint (Vander Heyden and al., 2017) and has been studied in developmental psychology since Piaget’s Three Mountains task (Piaget and Inhelder, 1956). Most studies have assessed SPT by asking children to look at a model layout of objects (one to four objects) and to judge, how an observer (a doll or a toy photographer) would see this layout from different angles (0 °, 90 °, 180 °, 270). The children have to choose the correct view from a set of photographs. These canonical orientations make it possible for the children to code the existing spatial relations between the scene and the observer in front-back and left-right relationships. The focus of the current study is to assess the effect of other orientations such as oblique (45, 135, 225°) in spatial reasoning. Indeed, the processing of stimuli whose orientation is horizontal or vertical is better than stimuli whose orientation is oblique (Gentaz & Hatwell, 1995 ; Gentaz & Streri 2004). Few studies concerning the development of SPT in children have explored this oblique effect. Using a playful (Animals and guardians of zoo have taken pictures) and increasingly complex learning situation (3 Spatial orientations, 16 animals, an internal and external point of view of the zoo) we examine the integration of different spatial orientations (front-to-back, left-right, oblique) during spatial reasoning in children aged 5 to 9 years. The results show a low number of errors and stable performance of children aged 7 to 9, regardless of the spatial orientation studied. In contrast, children aged 5 and 6 make more errors in judgment, especially for oblique orientation compared to other orientations (Anova chi2 (2, N = 95) = 13,5, p < 0.001). These results suggest a different sensitivity, depending on the age of the participants, to the characteristics of the tasks assessing spatial perspectives taking.