The influence of jamming on the performance of TACAN system is studied.Firstly, based on the models of effective navigation area under the blanketing jamming of radio-frequency noise and saturated asking jamming, the influence on the radius of effective navigation area of the beacon station under the action of single jammer and multiple jammers is analyzed.Secondly, the error of angle measurement under the envelope jamming of the same frequency and of different frequencies is deduced.Finally, the analysis results are verified by simulation.The simulation results show that:1) Multiple small-power jammers are more effective in affecting the navigation area of the beacon station than the single large-power jammer;2) The saturated asking jamming is better than blanketing jamming;and 3) The envelope jamming of the same frequency and of different frequencies will cause the error in accurate measurement interval, and about 40° angle measurement error will occur.