In order to study the effect of laser shock processing (LSP) in high temperature environment, the K417 superalloy is treated by LSP with laser power density of 8.5 GW/cm2 and pulse width of 10 ns, and then the Vikers hardness of K417 is tested after heat treatment at 700 ℃, 800 ℃ and 900 ℃, respectively. The results show that the hardening effect is weakened at elevated temperature, but the average hardness of LSP region is obviously higher than that of non-LSP region. With the temperature increasing, the thickness of the LSP hardened layer shows a decreasing trend and the hardness in the depth direction is fitted with exponential function approximately. The hardness distribution on a single laser spot is related to the laser shock wave′s inequality which is induced by the laser spatial distribution. The research indicates that LSP can raise the K417 superalloy′s comprehensive properties under 800 ℃.