Thermosetting polymers are popular due to their superior strength and high-temperature applications in comparison to thermoplastics. In the past few decades, various researchers have explored the promising ability of micro-/nano-fillers for the development of advanced thermoplastic polymer composites. Some commonly used techniques for the preparation of thermosetting polymer composites and their characterizations have been included in this article. The potential of thermosetting polymer-based composites in different application areas has been explored based on their characteristic features. These characteristics can also be used to indicate the structure-property relations of such composites. This article emphasizes the significance of thermosetting polymer matrix composites and possibilities for new developments in such composites for diversified applications.