Abstract Microstructural analysis is an important technique to study the extent of interaction between metal fillers and polymers. The aim of this study is to review the investigations on the microstructural properties of metal-reinforced polymer composites. Scanning Electron Microscope (SEM) operating at a magnification range of 2,500× is typically used for examining the microstructure of the composites. Microstructural analysis reveals two key qualitative informations, dispersion and interfacial adhesion. It was observed from the review that flaky metal fillers will maximise dispersion and interfacial adhesion hence leading to improved mechanical, tribological, electrical, and thermal properties of the composites. Utilizing ternary metallic components helps to eliminate aggregation because the cohesion of metal particles is limited. It is important that future microstructural studies evaluate nano-sized fillers as compared to micro-sized ones. Also, it is important to quantitatively correlate the arrangement of the fillers to macro-scale properties and finite element analysis is an important tool that can help achieving this.