This work investigates the difference between nanofibrillated cellulose (NFC) and bacterial cellulose (BC). BC possesses higher critical surface tension of 57 mN m-1 compared to NFC (41 mN m-1). The thermal degradation temperature of BC was also found to be higher than that of NFC, in both nitrogen and air atmosphere. These results are in good agreement with the higher crystallinity of BC based on area under the XRD spectra, measured to be 71% as compared to NFC of 41%. Both types of nanocellulose papers were found to possess similar tensile moduli and strengths of 12 GPa and 100 MPa, respectively. Nanocomposites were manufactured by infusing the nanocellulose paper with an epoxy resin using vacuum assisted resin infusion. The cellulose reinforced epoxy nanocomposites were found to possess a stiffness and strength of approximately ∼8 GPa and ∼100 MPa at an equivalent fibre volume fraction of 60 vol.-%. In terms of the reinforcing ability of NFC and BC in a polymer matrix, no significant difference between NFC and BC was observed.