Aiming at the problems of lack of instantaneity and low visualization in laser angle deception interference evaluation, the evaluation system for the airspace interference of false targets of laser angle deception interference was constructed. Firstly, the distance and attitude parameters of the false target of the diffuse reflector were calculated according to the principle of perspective projection, and then the interference mechanism of the false target of the diffuse reflector was analyzed and based on the interference distance, the airspace evaluation model of the false target interference of the diffuse reflector was derived. Finally, experiments were designed relied on the system. In the experiment, the diffuse reflector installed in the direction of 0°, 120° and 240° of the equipment was irradiated by lasers with different powers. Then the evaluation system equipment was used to measure the parameters of the three diffuse reflectors, and the average energy density received by the system were 2.70×10^-13 J/mm², 2.17×10^-13 J/mm² and 4.08×10^-13 J/mm²respectively. The maximum interference distance under 45° threat angle were 2045.6 m, 1860.4 m and 2470.0 m, respectively. Finally, the relationship between the size of the jamming airspace and the threat angle of the weapon was analyzed, and the situation maps of the interference airspace of the false target under the threat angles of 20°, 45° and 70° were obtained. The experimental results show that, under the experimental conditions, the interference airspace range of the false target increases with the increase of the energy received by the system. The smaller the angle between the attack direction of the weapon and the normal direction of the diffuse reflector, the greater the interference airspace. Taking the interference distance as the evaluation index, the interference airspace of the diffuse reflector false target is evaluated, which can provide technical support for the interference effect evaluation of false target.