Abstract: The correlation variation of acoustic propgation channel is mainly caused by time space variation of the multipath structure of acoustic channel. In general, acoustic channals in deep sea have more simple multipath structure due to less influence. of the sea bottom. So in deep sea the correction match of acoustic channel could be more easy realized. In this experiment, a towed powerful low freqency transducer is used to transmit linear freqency modulated pulse, and at the receiving terminal the copy correlation and the pulse to pulse correlation were used to obtain the time space variation of acoustic channel correlation. Du to the application of wide band, long duration pulse and signal processing, the noise influence is reduced to minimum.Therefor our experimental.results proved that the time space correlation of acoustic channel is mainly determined by the time space variation of channel's multipath structure, and coherent part of such a multipath channel makes up about 40 per cent of its total. The experimental results described in this paper could be helpful to study the correction match of the deep sea acoustic channel.