Research Findings: The Children’s Social Understanding Scale (CSUS) assesses young children’s theory of mind (ToM). The current study adapted the parent version of the CSUS-short form to Turkish and examined its utility, for the first time, as an assessment tool for teachers. The associations of parent and teacher reports of the CSUS-short form with classical behavioral assessments of ToM were investigated along with such known correlates of ToM as receptive language, executive functions (EF), and social competence. Two hundred and two children (Mage = 53.98 months), their parents and 169 teachers participated in the study at Time 1, and one year later at Time 2, 132 parents and 109 teachers completed the CSUS-short form again. Similar to the original version of the scale, both parent and teacher forms yielded one-factor structure, demonstrated high internal consistencies at both measurement points, and were positively correlated with each other across time. Parent and teacher forms were also concurrently and positively associated with behavioral ToM tasks, receptive language, EF, and social competence. Practice or Policy: These results pointed to the reliability and validity of the parent and teacher versions of the CSUS-short form as a multi-informant measure for Turkish preschoolers and lay the ground for cross-cultural comparison of children’s ToM scores with the other cultural adaptions of the CSUS.