The cellulose is made up of long chains of polysaccharide of glucose molecules. Microfibrils are formed when numerous hydrogen-bonded cellulose chains unite, they are extremely stiff and contribute to physical stability, due to this general ability of forming these microfibrils to form long chains, cellulose is an ideal molecule for the manufacturing of packaging materials and bioplastics. On the other hand, Invasive plant species are one of the major constituents for environmental degradation and its application seems outmost. The main purpose of this study is to extract and identify the composition of cellulose fiber and characterize the fiber of invasive plant species that could be used as a replacement for plastics and textiles in some cases. In this study, Cellulose was isolated from 6 invasive species collected in Nepal's Ramechhap district using various techniques, the composition of the fiber was identified using AOAC method 973.18, ASTM method D1106-96 and ASTM method E1755-01 and characterized using FTIR spectroscopy with weight analyses. Acid hydrolysis, chlorination, alkaline extraction, and bleaching were among the chemical methods adopted. In all of the samples, there were two primary absorbance peaks. The first occurred at low wavelengths in the 700−1, 800 cm−1 range, while the second occurred at higher wavelengths in the 2,700–3,500 cm−1 range. The percentage of lignin within the final sample was determined in the range of 4.4-3.1% and the percentage yield of cellulose was determined within the range of 78-62%. The study shows that the cellulose can be extracted from the taken invasive plant species and can be used for further applications.