The setting of the jamming lead has an important influence on the success probability of laser angle deception jamming. By establishing the probability model of the guidance signal in the laser angle deception jamming and the probability model of the jamming signal being accepted by the wave gate, the optimal jamming lead formula was deduced and verified. The influence of different factors on the optimal jamming lead setting was studied by simulation. The simulation results show that the gate width, the guidance signal interval error and the jamming signal interval error have great influence on the setting of the optimal jamming lead. The optimal jamming lead is proportional to the width of the gate. The larger the guidance signal pulse interval error is, the smaller the jamming signal pulse interval error is, and the larger the optimal jamming lead is. The jamming probability of laser angle deception jamming can be greatly improved by setting the appropriate jamming lead.