Pretend play may be beneficial for young children's social development. However, empirical results to date are inconsistent and limited, which is partly due to a lack of psychometrically sound measures for children's social pretend play competence. The current study aimed to compare and validate different assessment methods for children's social pretend play competence. In total, 64 3- to 4-year-old children participated in the study (age: M = 46.4, SD = 3.8). Assessments were conducted twice, three months apart. Social pretend play competence was assessed using a standardized role play test (Tools of the Play Scale), a social pretend play situation with a peer (Dyadic Pretend Play Assessment), and a teacher report. Children's Theory of Mind, emotion understanding, and language comprehension were assessed. Educators reported on children's social-emotional skills. Research Findings: All three instruments showed a good factorial validity, measurement invariance and sensitivity to intra-individual change. A second-order factor of all three methods was identified. The Tools of the Play Scale and the teacher report yielded good criterion validity. The second-order factor showed even better criterion validity: Children with higher social pretend play competence showed higher social-cognitive skills as well as social-emotional skills. Practice or Policy: Limitations and applications of the instruments are discussed.