Abstract In this study, the plant and waste fibers (pineapple leaf fiber, banana fiber and recycled disposable chopstick fiber) with an average length from 2.3 to 3.9 mm were chemically modified by 3-aminopropyltriethoxysilane (A1100). Subsequently, these modified fibers (20 wt.%) and epoxy resin were mixed and cured to form novel fiber-reinforced green composites. The results showed that the decomposition temperatures of the chemically modified fiber-reinforced composites were obviously higher than those of untreated fiber-reinforced composites. In addition, the tensile strengths of the reinforced epoxy composites could be increased from 80% to 117% as compared to that of the pristine epoxy. Moreover, the modified pineapple leaf fiber-reinforced composites exhibited better thermal properties than did other reinforced samples. On the other hand, modified recycled disposable chopstick fiber-reinforced composites possessed pronounced mechanical properties.