Abstract: For features of low frequency and low bit rate of elastic wave through-the-earth communication system, a time-division multiple channel segment sliding correlation acquisition method was proposed. The method receives arrived code element in segment, and uses time of receiving next segment code to deal with previous received code segment, namely 1 PN code period is divided into several channel time slots, each time slot carries out fast sliding correlation search between previous received PN sequence segment and local PN code of channel. The theoretical analysis result shows the time-division multiple channel segment sliding correlation acquisition method can get almost the same search speed with parallel acquisition when its hardware cost is the same to serial parallel search. The simulation result validates validity of the acquisition method.