Physicochemical/thermal modifications on the organic fibres increase the cellulose exposure, potentially improving the thermo-mechanical properties of the composites. This work aims to investigate the thermo-mechanical properties of hemp fibres and their composites to understand the effect of the proposed novel cryogenic treatment using physicochemical characterization like scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Fourier transmission infrared spectroscopy (FTIR). The study compares them with conventional dual alkali-anhydrous treatment on the fibres. Dual alkali-anhydrous treatment on the fibres didn’t change its thermal properties, but specific chemical changes were detected. In comparison, investigations of cryogenic treatment on fibres showed improved thermal stability and wettability due to increased cellulose exposure in the primary cell wall. It also reduced the moisture absorption in the fibres. Improvement in mechanical properties was observed in cryogenic treated hemp composite due to increased frictional bond in the composite interface. Hence the proposed cryogenic treatment provides new directions for developing bio-composites for potential engineering applications like automobile interiors and insulation panels in mining applications.