Abstract: Traditionally, in the simulation of radar network, the aircraft is regarded as a point, whose RCS(Radar Cross Section) is constant; In fact, the RCS is a function of the frequency of radar and the angle between the aircraft and radar. Radar targets characteristic database is created by creating the electromagnetic model of targets, calculating the RCS of the angles and frequencies, storing the data in a database. The radar network simulation system is established composed of center computer, radar targets characteristic database, and several radars. The simulation results indicate that: the results of simulation in which the RCS of aircraft is changed, using the target characteristic database, than fixed, are more creditable; radar network increases the detected probability of radars greatly.