Based on the target reflection section defined by The Bidirectional Reflectance Distribution Function, a method of approximate calculation and analysis of the cone and plate’s reflection section in laser-illuminated condition are derived in the paper. With the method, reflection section of cone is calculated and analyzed. Experimental platform was established with 1.319m Nd:YAG laser, measuring the reflection section of cone in diverse incident angle. Curve of the plate, cylinder and cone relative illumination changing in diverse incident angle were measured. The results of this study are helpful for many applications such as weapon designing, target invisible, and system modeling.