The invention provides a dielectric interface amplitude compensation method and device. the method comprises steps: according to to-be-analyzed seismic data, a root mean square amplitude value of a seismic trace is acquired; a dielectric interface is picked up, and according to the root mean square amplitude value of the seismic trace, an interface reflection amplitude value corresponding to the dielectric interface is calculated; according to the interface reflection amplitude value and a preset seismic energy general value, an interface transmission amplitude value corresponding to the dielectric interface is calculated; according to the interface transmission amplitude value, an interface amplitude compensation factor is calculated; and according to the interface amplitude compensationfactor and the root mean square amplitude value of the seismic trace, dielectric interface amplitude compensation operation is carried out. By using each embodiment in the invention, compensation on the amplitude at the dielectric interface is realized, the seismic data after amplitude compensation more truly reflect changes of underground geology, an accurate data base is provided for processingand interpretation of subsequent seismic data, and the seismic data processing result accuracy is improved.