Objectives Although a number of early childhood development (ECD) interventions in healthcare settings in low- and middle-income countries (LMICs) have been developed to improve parent-directed outcomes and support ECD, their impact have yet to be established. This review assesses the effectiveness of healthcare-based ECD interventions in LMICs on the following key evidence-informed parenting outcomes affecting ECD: (1) responsive caregiving (2) cognitive stimulation and (3) parental mental health. Impacts on parental knowledge regarding ECD and parenting stress were also assessed. Methods PubMed, PsycINFO, Scopus, CINAHL and Embase were searched. We included randomized controlled trials reporting effects of healthcare-based ECD interventions in LMICs on parent-directed outcomes in the first five years of life. Data extraction included study characteristics, design, sample size, participant characteristics, settings, intervention descriptions, and outcomes. Meta-analyses were conducted using random effects models. Results 8 articles were included. Summary standardized mean differences demonstrated significant benefits of healthcare-based interventions in LMICs for improving: (1) cognitive stimulation (n = 4; SMD = 0.32; 95% CI: 0.08 to 0.56) and (2) ECD knowledge (n = 4; SMD = 0.44; 95% CI: 0.27 to 0.60). No significant effects were seen on maternal depression and parenting stress; only one study assessed parent-child interactions in the context of responsiveness. Limitations included small number of studies for moderation analysis, high heterogeneity, variability in measures used for outcomes and timing of assessments. Conclusions for practice Our results demonstrate statistically significant effects of healthcare-based interventions in LMICs on improving key evidence-based parenting outcomes and offers one promising strategy to support children reach their full developmental potential.