The literature revealed that 70–80% of South African small businesses, including informal micro-enterprises, fail in the first year of their existence. Innovation has been recognized as a catalyst that can enhance informal micro-enterprises’ probabilities to survive and transform them from survivalists to sustainable businesses that grow the economy and create jobs. As far as it can be reasonably determined, there has not been a systematic review of the literature on innovation activities of informal micro-enterprises in the Gauteng province, South Africa. This study aims to present a systematic review of the literature, as well as research gaps identified in the literature, and future research opportunities. This paper thus systematically reviews the literature on innovation activities of informal micro-enterprises in the Gauteng province. The study revealed that the innovation capacity of informal micro-enterprises is severely hampered by innovation tradition and social tax. Subsequently, informal micro-enterprises engage less in innovation activity and those that do innovate often engage in incremental rather than radical innovation. Radical innovations are more crucial than incremental innovations. Thus, there is a need for researchers and government organizations to establish initiatives that can aid the informal micro-enterprises to engage more in radical innovation.