Abstract: Highly integrating with electronic system and depending on information link, unmanned aerial vehicle (UAV) is vulnerable to external electromagnetic interference (EMI). Due to the large-scale application of UAV in modern electronic warfare, its electromagnetic safety poses a serious challenge. In this paper, analyzing the coupling path to electromagnetic interference, an ideal model of UAV information link to EMI was established to studying the suppression of EMI on work signal of the data link system. Firstly, taking a kind of UAV data link system as the research object, a ground simulating test method was proposed for UAV information link in dynamic flight. Then an experimental system was established to study the EMI injection effect of data link system, and to get the electromagnetic sensitivity criterion. Finally, a series of continuous wave EMI injection experiments were carried out for UAV uplink system. Based on the experiment results, the sensitive frequencies and their electromagnetic sensitivities were found, the mechanism of electromagnetic interference for information link was analyzed, and the relationship among the effect of lost-link, automatic gain control (AGC) voltage and bit error rate (BER) was achieved. The research results can provide an experiential reference for range experiment and electromagnetic interference prediction of UAV.