Infrastructure as an asset class has emerged as a new field of research stemming from the broader universe of infrastructure investment. Since the advent of the global financial crisis, research activities in this area are constantly strengthening providing the base for a budding research area. Despite much work done, infrastructure investment research with regard to an asset class is still at an early stage and scholarly understanding remains restricted and fragmented. To get a clear understanding of this rather opaque field, and for further advancement of scientific research, we conduct a systematic literature review and thematic analysis of 89 scientific contributions including 71 journal articles, 15 working papers and 3 conference papers published during 1997–2021. Based on a holistic examination of identified articles, we elucidate the current infrastructure investment landscape targeting two major aspects: First, we descriptively analyse the convergence of infrastructure from mere assets to an asset class. Second, we categorize the existing research into four different perspectives: capital market, investment performance, policy and stakeholder and conduct a thematic analysis to unveil major themes and sub-themes under each perspective. Furthermore, the study attempts to suggest various promising future research avenues to encourage further expansion of infrastructure investment as a research field.