The present study investigates the influence of hygrothermal ageing on the tribological behaviour of polytetrafluoroethylene (PTFE) polymer composites. Three PTFE composites along with unfilled PTFE were tested in sliding contact against Inconel 625 (a Ni-based alloy) plates in both dry and water-lubricated conditions, utilising a unidirectional pin-on-disc tribometer. The tribo-tests were performed at a constant sliding speed of 0.13 m/s with a normal load of 84N providing an apparent contact pressure of 5 MPa. Hygrothermal conditioning was carried out at two different temperatures, and the water absorption evolution and kinetic parameters were estimated. Various characterisation methods were used to identify the wear mechanisms and influence of hygrothermal ageing on the degradation of the filler/matrix. The different tribological behaviour for different PTFE composites was observed within the ageing timeframe. The wear resistance of the fibre-filled samples was reduced compared to the non-aged ones over the ageing timeframe. However, the friction and wear resistance of the bronze-filled PTFE were enhanced by hygrothermal ageing.