ABSTRACT This thesis is aimed to investigate the fatigue life, strength, damage and fracture process in AS-4/PEEK APC-2 composite laminates subjected to both elevated temperature and loading sequences. Our main work is experiment. All specimens are 16-ply thick with lay-up of quasi-isotropic laminates. We accomplish static tensile test, fatigue test of constant stress amplitude, and two-step loading at elevated temperatures, i. e., 75¢Jand 125¢J. The residual strength and stiffiness are obtained. We also use Miner¡¦s rule to analyze the data acquired from experiment and to discuss the fatigue properties and fracture mechanism subjected to both elevated temperatures and loading sequences of combination. Finally, we perform ultrasonic C-Scan non-destructive test to examine laminates. In comparsion with experimental data, we can further understand the damage process and fracture mechanism in laminates. The experimental results can be concluded as follows. The damage of specimens at 125¢J is more serious than that at 75¢J.Furthermore, if the loading sequence is low-high, the cumulative damage value will be smaller than 1,whilst it will be larger than 1 due to reverse loading sequence. The sequence of decreasing residual strength and residual stiffiness of specimen associated with the temperature and stress level in combination is high temperature¡Ðlow stress, low temperature¡Ðlow stress, high temperature¡Ðhigh stress and low temperature¡Ðhigh stress.