The German version of the Perception of Inclusion Questionnaire (PIQ), which is used to assess students' emotional inclusion, social inclusion, and academic self-concept, was analyzed with the multi-unidimensional graded response model (GRM) and investigated for differential item functioning (DIF) between students with and without learning difficulties (LD). The PIQ was administered to 823 primary school students in Switzerland (Mage = 11.94, SD = 1.01 years), of which 190 were classified as having LD. Results show that the PIQ is a reliable instrument for assessing students' perceptions of their inclusion at school, especially in the lower ranges of the scales. No bias was detected for any items of the PIQ's three scales in relation to the exogenous variable LD, with the exception of one item that showed a minor deviation.