To estimate the jamming effect of high repetition laser on laser seeker′s decoding effectively， two quantized model were adopted, which were concerning to code distinguishing stage and code locking stage respectively. During simulation, the research emphasis was put on the effect of laser frequency on the laser seeker which adopted anti-interference technology. The simulating results show that the jamming effect is affected by laser frequency, coding pattern, sampling period, the width of time-gate, and so on. And the jamming effect during code distinguishing stage is better than code locking stage, but both stages could be jammed successfully when the frequency become higher than a certain value.