Abstract: In order to investigate velocity and angle effects of light flash radiation produced by hypervelocity impact, experiments have been conducted under six kinds of experimental conditions by using an optical pyrometer measurement system and a two-stage light-gas gun loading system. Each experiment used anoptical fiber probe. The relationship of impact velocity and projectile incidence angle was obtained for hypervelocity impact on LY12 aluminum target, based on original data and calibration by Matlab programmable treatments under given experimental condition and optical fiber probe scheme. Experimental results show that, during hypervelocity impact, the impact light flash radiated temperature is approximately proportional with the square of product of impact velocity and sine of projectile incidence angle (angle between trajectory and target plane) before the radiated temperature reaches its peak, and then it is approximately proportional with the 0.75 power of the product of impact velocity and sine of projectile incidence angle after the peak appearing, which is basically identical with the theoretical derivation.