Although parental sensitivity is an established determinant of children's attachment security, effect sizes are modest, suggesting other aspects of parenting that might support secure attachment. Parental emotion socialization (ES) has been proposed as a parenting domain that is theoretically linked to secure parent-child attachment. The goal of this meta-analysis was to evaluate the strength of the relations between parental ES and attachment security in children under the age of 18. We conducted three meta-analyses assessing the links of supportive parental ES, nonsupportive parental ES, and parental elaboration with attachment security assessed with behavioral, representational, and questionnaire measures (ks = 9-11 samples; Ns = 576-1,763 participants). The relation between supportive ES and security was significant but very small (r = .06). The relation between nonsupportive ES and security was not significant (r = -.05). Parental elaboration emerged as a key correlate of secure attachment, with a medium effect size (r = .24), similar to the relation between sensitivity and attachment security. The findings underscore the need for further research to elaborate on the role of ES in the development of attachment. (PsycInfo Database Record (c) 2025 APA, all rights reserved).