ABSTRACT Global warming is a serious environmental issue that is mostly caused by the release of greenhouse gases into the atmosphere, resulting in higher global temperatures, climate change, and more severe natural disasters. As we all know, cement is the most common binder material in the construction sector. Globally, this industry is contributing about 7 to 8% of total CO2 emissions, making it the second largest source of greenhouse gases. Nevertheless, the production of cement continues to increase at a rate of 3 to 4% each year. Simultaneously, a large amount of industrial waste, rich in alumina and silica, is produced annually, yet the majority ends up in landfills. However, this waste has the potential to be used in the synthesis of geopolymers, giving a greener alternative to traditional cement binders. Geopolymers made from aluminosilicate-rich precursors using alkaline activation have received a lot of attention since they can cut energy usage by about 60% and CO2 emissions by up to 90% when compared to ordinary Portland cement. Among the aluminosilicate-rich precursors, coal fly ash is one of the potential source materials that can be found in abundance. Therefore, the present study uses fly ash as a source material and a combination of NaOH and Na2SiO3 solution as an alkali metal oxide activator. In this study, a new geopolymer composite material was produced using fly ash and false banana plant fiber. Furthermore, the synthesized composite material as well as the false banana fiber was exposed to a variety of harsh environments for varying durations in order to evaluate its long-term performance. Different techniques such as XRD, SEM, FTIR, density measurement, ultrasonic pulse velocity test, and mechanical strength analysis were used to evaluate its performance. Results showed that the maximum compressive and splitting tensile strengths of the composites were about 33 and 6 MPa, respectively, for the corresponding optimal parameter settings. Based on the durability analysis, both the geopolymer composite and the false banana fiber are highly sensitive when exposed to a strong acid solution, putting their long-term performance in such environments into question. Overall, the findings of this research project provide basic information about natural fiber reinforced geopolymer matrix composite, their processing and properties, which will enable further research on their important novel class of sustainable materials. Keywords: Fly ash, False banana fiber, Geopolymer composites, Mechanical properties, Microstructure analysis, Performance evaluation.