Background: Social capital is defined as social relations that may provide individuals and groups with access to resources and supports in community networks. It has become an important issue to be studied in the field of public health. This study aimed to review pieces of literature about the role of social capital on the utilization of maternal and child health services in low- and middle- income countries.Methods: Mixed-methods research review and synthesis, using three databases (PubMed, Scopus, and Science Direct), was performed. Besides, Google Scholar and Google search engines were used. Both quantitative and qualitative studies conducted in low- and middle- income countries, published in English, in grey and commercial literature were considered. Results: A total of 1,545 studies were identified, of which, 328 records were removed due to duplication. Then, 13 records were selected after reading titles, abstracts, and full texts. Of these eligible studies, six studies were included for quantitative synthesis, and seven of them for qualitative synthesis. Moreover, six quantitative studies and seven qualitative studies were included. Of the six reviewed quantitative studies, five of them addressed the relationship between social capital and health facility delivery. Likewise, women who lived in communities with higher membership in groups that help form intergroup bridging ties had higher odds of antenatal care use. Synthesized qualitative findings revealed that women received some form of emotional, informational, and instrumental support from their network members. Receiving health information from trusted people and socio-cultural factors influenced the use of maternal health services.Conclusions: Social capital has a great contribution to the utilization of maternal and child health services. Countries aiming to reduce maternal mortality should identify context-specific approaches to benefit from its social capital. On the other hand, measurement tools for social capital require due attention as there is no uniformity across studies and most of them were conducted using a cross-sectional design. Hence, further longitudinal and interventional studies should be employed to pin down the direction of causality.Systematic review registration: PROSPERO CRD42021226923