Abstract: The injection of laser energy will change the wave structure and effectively reduce the pressure load on the blunt body surface. A high resolution numerical method based on finite volume method and domain decomposition of structural grid is used to compute the influence of laser single pulse energy and laser continuous energy injected into type Ⅳ shock interaction at Mach number 3.45.The result shows that the pressure on the blunt body surface increases slightly when the injection laser energy with a single pulse is in a relatively short period(50 s to 60 s ),then it declines quickly, and it restores to the original state at last. The peak of the pressure on the blunt body surface increases slightly after the injection of a little laser energy with continuous deposition, and then decreases quickly with the increase of the laser energy deposition. It is remarkable that the peak of the pressure decreases slowly and tends to be a constant value even the laser energy deposition increases again.