Radio Frequency (RF) stealth radar can improve the electronic defense capability of radars fundamentally,which is a research hotspot of current aviation equipment,and the key of it is the design of RF stealth signal.Anti-sorting signal is an important RF stealth signal,and the design method of anti-sorting signal is one of the difficult points in RF stealth signal design.By analyzing Sequential Difference Histogram (SDIF) sorting algorithm,the main sorting algorithm of Radar Warning Receiver (RWR) and other real-time electronic reconnaissance equipment,the failure principle of Pulse Repetition Interval (PRI) estimation error is pointed out when PRI signal changes rapidly in a large range.Then,an anti-sorting signal design method for RF stealth radar based on pulse group agility is proposed.In other words,through PRI stride agility of pulse group signal,the main sorting algorithm output of RWR and other real-time broadband electronic reconnaissance equipment may produce large error or even complete error.Simulation and experiment prove that the signal designed based on the above method can effectively counter RWR main sorting algorithm,and the objective of radar anti-sorting is achieved.