The main objective of this work was to investigate the effect of cellulose as modifier and the drawing ratio on the thermal and mechanical properties of drawn polypropylene (PP) fibres. The modification of PP fibres during their production can helps to prepare PP fibres with improved properties, guarantees new opportunities for the expansion of an assortment of PP fibres in the clothing and domestic textile industries. PP fibres were prepared from PP pellets and PP/cellulose masterbatch via the melt spinning technique at 260 °C followed by drawing for various draw ratios. Differential scanning calorimetry (DSC) was used to evaluate the thermal properties of PP fibres. The mechanical properties (tenacity and elongation at break and modulus of elasticity) and low-cycle loading of modified PP fibres were also studied. The obtained experimental results of drawn modified PP fibres were compared with unmodified PP fibre prepared under the same technological conditions.