Objective: To test the psychometric properties of the Spanish version of the Self-Care Self-Efficacy Scale (SCSES-Sp) in community-dwelling older adults with chronic multimorbidity. Methods: A sample of 1013 community-dwelling older adults with chronic multimorbidity participated in an observational cross-sectional study that was carried out in 3 phases. Results: Confirmatory factor analysis showed that the SCSES-Sp has 4 dimensions: "self-efficacy in self-care behaviours based on clinical knowledge", "self-efficacy in self-care maintenance", "self-efficacy in self-care monitoring", and "self-efficacy in self-care management". A panel of independent experts considered the content of the SCSES-Sp valid. Convergent validity analysis showed moderate-strong correlations between all of the SCSES-Sp's dimensions and the reference criteria chosen. Reliability was good for the SCSES-Sp and all its dimensions. Test-retest reliability analysis showed that the SCSES-Sp was temporally stable. Conclusions: The SCSES-Sp is a valid and reliable tool to assess self-efficacy in self-care in Spanish-speaking, community-dwelling older adults with chronic multimorbidity. © 2023 The AuthorsMinisterio de Ciencia e Innovación, MICINN, (AEI/10.13039/501100011033)