In view of the challenges involved in designing a study of Mixed Methods (MM), as well as the problematics inherent in studying Service-Learning (S-L) from new research perspectives, and considering the lack of systematic reviews of MM in S-L, this study proposes to analyse the use of MM research to evaluate S-L through a systematic integrative review of scientific papers published in international databases (ERIC, DIALNET, SCOPUS, and Web of Science) using the terms ‘mixed methods research’ and ‘service-learning’. The contextual and methodological variables were analysed descriptively and inferentially using Excel and Stata programs. Moreover, 149 predefined codes were created and analysed using the qualitative program Atlas.ti to identify which terms associated with the research methodology were used most frequently in relation to the MM for S-L methodology, and how and why they were used. Of the 192 papers found, only 93 met the inclusion criteria. The results show that very few investigations specify the MM they used in sufficient detail. Only 28% provide information to estimate the effect size, suggest interventions based on S-L, and collect measures for post-intervention evaluation. This demonstrates that the relationship between MM and stages of the S-L are not complemented in the methodological design. The results demonstrated that researchers should continue working with MM in S-L for the integration of qualitative and quantitative results. This research can be a methodological guide for professionals and academics who want to investigate MM in S-L because it identifies methodological deficiencies and strengths and offers and alternative designs to evaluate the service.