Due to the high strength-to-weight ratio and excellent corrosion resistance of aluminum alloys, they have been widely used in the aerospace and rail transportation industries. The Portevin-Le Chatelier (PLC) effect, a class of plastic instability frequently observed in aluminum alloys, is a typical multiscale phenomenon. Macroscopically, the PLC effect manifests itself as the serrated flow on stress-strain curves and highly-localized deformation bands on the sample surface within a certain range of temperature and strain rate. Microscopically, this phenomenon is related to the interactions between dislocations and mobile solute atoms. The PLC effect may occur at room temperature, increasing the surface roughness while decreasing the necking strain in aluminum alloys. The resulted degeneration of material formability and ductility restricts their practical applications to a certain extent. Therefore, a deep insight into the PLC effect in aluminum alloys has important theoretical and industrial meanings. In this paper, the latest research progress of the PLC effect was reviewed from four aspects for aluminum alloys, including characteristics, theoretical explanations, influencing factors, and research tendency. Firstly, three classical types of the PLC effect were introduced, with an emphasis on their classification criteria, basic features, and the transitions between different types. Secondly, the general interpretations of the PLC effect were summarized, with an interest in the historical development of the dynamic strain aging theory. Thirdly, the effects of temperature, strain rate,grain size, and precipitates on the PLC effect of aluminum alloys were discussed in details. Finally, a brief prospect of the PLC effect in aluminum alloys was proposed.