The invention discloses an amplitude spectrum method for automatically calculating a seismic data cable coupling noise intensity degree. The method comprises steps that step 01, single-channel data which is acquired by a DAS and is recorded by a VSP is read; step 02, fast Fourier transform of the single-channel data of the step S01 is carried out, and conversion from the time domain to the frequency domain is carried out; step 03, normalization processing on a discrete sampling value X[k] of the frequency domain is carried out; step 04, variance or a peak degree of normalization amplitude spectrum is calculated; and step 05, the steps 01-04 are repeated till all the channel data is processed. The method is advantaged in that a sparse optimization algorithm parameter is selected based on the cable coupling noise intensity degree, cable coupling noise can be adaptively inhibited, an automatic cable coupling noise intensity degree calculation problem in the DAS seismic data can be solved, and accurate single-channel calculation is realized.