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In this paper,we developed a multi‐step multi‐order numerical difference method to detect theTraveling ionospheric disturbance(TID).This method can eliminate TEC trend effectively and has a wide span of detectable periods.In this study,the principle of the multi‐step multi‐order numerical difference method is presented firstly.Then,we execute three experiments with the simulated data and real data to test the feasibility of the method: the first experiment using the simulated TID signal without the TEC trend,the second one with real TEC observations but simulated TID signals and the last one having real TEC observations and TID waves.The experimental results demonstrate (1) detected TID wave has the same frequency compared to the true signal and the ratio of amplitude between them is also consistent with the theoretical result; (2) distinct to first‐order method,the second‐order difference process can eliminate trend term effectively even when TEC varies drastically; (3) this method can detrend TEC and extract TID signals simultaneously and can detect multiple disturbances with various periods.