In order to investigate the effect of laser shock peening (LSP) and heat treatment on the surface properties of TC4 titanium alloy, LSP was applied to TC4 titanium alloy specimens. The surface hardness and corrosion resistance of the surfaces before and after LSP and heat treatment were analyzed by using microhardness tester and an electrochemical workstation. The surface and cross-sectional morphology and microstructure were analyzed through laser confocal microscopy and SEM. The results show that the surface hardness of the specimens strengthened by one and two LSP impacts reached 425.4 HV and 456.5 HV respectively, an increase of 12.3% and 20.5% compared to the original specimen. After heat treatment, the surface hardness of specimens further increased to 465.1 HV and 483.2 HV respectively. The self-corrosion potential was positively shifted and the corrosion current density decreased after LSP. The corrosion rate of the specimens was reduced by 36.2% and 4% compared to the original specimen after one and two impacts, respectively. After heat treatment, the self-corrosion potential of TC4 specimens shifted negatively, the corrosion current density increased, the corrosion rate increased, and the corrosion resistance decreased.