In this work, the effect of temperature exposure on the strength of resistance welded joints is analysed. Glass fibre polyphenylene sulphide (GF/PPS) laminates were joined using the resistance welding technique and a stainless steel metal mesh as the heating element. Single lap shear tests at temperatures between 20°C and 150°C were performed to evaluate the strength of the welded joints and fractography was used to investigate changes in the failure mechanisms at elevated temperatures. The results show a strength reduction of 10-15% for the samples tested at temperatures up to 90°C, and a strength reduction of 22% and 38% for the samples tested at 120°C and 150°C, respectively, while the fracture surfaces observation revealed changes in the failure mechanisms of the welded joints tested at elevated temperatures.