Empathy is an important social construct that has been defined in many ways by different authors, resulting in development of several questionnaires. The Interpersonal Reactivity Index (IRI) is one of the most used self-report scales to measure empathy in children, adolescents, and adults. However, studies have reported contradictory results about its factor structure. Therefore, the aim of the current study was to assess the dimensionality of the IRI through a meta-analytic structural equation modeling approach (MASEM). Eleven studies (total n = 9470) were included in the MASEM. The meta-analytic confirmatory factor analyses (CFAs) provided support for four of the tested models. A comparison of these models showed that the four-factor model proposed by Lucas-Molina et al. (2017) had the best fit. Overall, this MASEM suggests that the IRI provides a multidimensional, rather than a unidimensional, measurement of the empathy construct.