ObjectivesIntegration of oral health into primary care has been proposed as a primary healthcare approach for efficient and sustainable delivery of oral health services, and the effective management of oral diseases. This paper aimed to synthesise evidence on the effectiveness of strategies to integrate oral health into primary care.DesignSystematic review.Data sourcesMEDLINE, CINAHL, Embase, Scopus, ProQuest, Cochrane and Google Scholar were searched without date limits until the third week of June 2022. Reference lists of eligible studies were also searched. Experts in the field and existing professional networks were consulted.Eligibility criteriaOnly studies that evaluated integration strategies were included in the review. Eligibility was restricted to English language studies published in academic peer-reviewed journals.Data extraction and synthesisTwo reviewers independently extracted data and performed the risk of bias assessments. A narrative synthesis approach was used to report review findings. Heterogeneity among included studies precluded a meta-analysis.ResultsThe search identified 8731 unique articles, of which 49 were included in the review. Majority of the studies explored provision of oral healthcare by primary care professionals in primary care settings, where integration was primarily via training/education and/or policy changes. Most studies reported results favouring the integration strategy, such as improvements in referral pathways, documentation processes, operating efficiencies, number of available health staff, number of visits to non-dental primary care professionals for oral health issues, proportion of children receiving fluoride varnish applications/other preventive treatment, proportion of visits to an oral health professional and dental caries estimates.ConclusionThe findings from this review demonstrate that the majority of identified strategies were associated with improved outcomes and can be used to inform decision-making on strategy selection. However, more research and evaluation are required to identify best practice models of service integration.PROSPERO registration numberCRD42020203111.