In this paper, elastic-plastic finite element analysis has been performed in order to obtain the fatigue crack tip parameters under tension-compression loading. Two centre-cracked high-strength aluminum alloy with a crack length of 2mm under different tension-compression loading are analyzed. The analysis shows that the compressive loading has a significant contribution towards the crack tip plasticity and the crack tip stress. In a tension-compression loading the crack tip displacement increases with the increase of the compressive stress and the crack tip compress stress increases with the increase of the compressive stress. The maximum stress intensity Kmax in the tension part of the stress cycle and the maximum compressive stress in the compression part of the stress cycle are the main factors controlling the near crack tip parameters.