Polymer gears have emerged as a potential replacement of metallic gears in low load applications. It has happened due to the inherent properties possessed by polymeric materials. These properties include low inertia, noiseless operations, better stiffness and others. In this study, the temperature and wear performance of two different polymer composites gears, viz. carbon-fiber-filled high-density polyethylene (HDPE/CF) gears and polyoxymethylene (POM/CF) gears, have been investigated. The gears used in this study are injection molded. The different weight percentage (0%, 5%, and 10%) of the reinforcements are considered for producing the composite gears. The gears are tested at different loading torques varying in a range from 1 Nm to 2.5 Nm. Results show that HDPE gear filled with 10% CF provides the best thermal performance, whereas the best wear performance is achieved by POM gear filled with 5% of CF.