Thermal cracking is one of the major distresses in a pavement structure. One solution to combat this issue is by employing polymer fibre as an additive. This paper presents an extensive observation of the fracture behaviour of fibre-reinforced warm mix asphalt, characterized by crack resistance index (CRI) and flexibility index (FI) retrieved from Semi-Circular Bending tests conducted 0°C. Three different fibre dosages and two different fibre lengths are examined herein. The outcome reveals that the rise of fibre dosage and length is inversely proportional to the progression of CRI due to the intensification of the brittleness of the specimen. Furthermore, FI indicates the importance of fibre during the post-cracking stage, where the integrity of a specimen is mainly determined by the network of the fibre. Finally, the mechanical properties of the specimen supplemented with 38-mm fibre at 0.1% w/t are commensurate with that of 19-mm at 0.5% w/t.