This study deals with the characterization of a natural fiber which is extracted from the stem of an unexplored plant ofCyperus platystylisR.Br. (CPS) with an aim to establish it as a potent alternative fiber for the plant fiber-based industries. CPS fiber has been investigated for its physical, chemical, thermal, mechanical, and morphological characteristics. The presence of different functional groups in CPS fiber i.e., cellulose, hemicellulose, and lignin which was ensured by Fourier Transformed Infrared (FTIR) Spectrophotometer analysis. X-ray diffraction and chemical constituent analysis revealed high cellulose content and crystallinity i.e., 66.1% and 41.12% respectively, which is comparatively moderate in the case of CPS fiber. Scherrer's equation has been used to determine crystallite size i.e., 2.28 nm. The mean length and diameter of the CPS fiber were 382.0 and 23.36 μm, respectively. The maximum tensile strength was obtained at 657 ± 58.8 MPa for 50 mm fiber and young’s modulus 88.76 ± 30.42 MPa for 50 mm fiber. The required energy to break has been recorded at 346.16 J. Thermal analysis revealed that CPS fibers have thermal stability up to 279 °C. The uniqueCyperus platystylisstem fibers could therefore be a suitable reinforcement material for the bio-composites used in semi-structural applications since they have higher functional qualities.