In view of the lack of geological investigation and the lack of existing geophysical survey methods on Intertidal zone, the technical research of shallow reflection seismic exploration method is carried out in the tidal flat area of Rudong County, Nantong City, Jiangsu Province. The shallow reflection of seismic detection using hammer source and the natural frequency of 60 Hz detector. Through the experiment, the reasonable parameters of the observation system and the instrument are determined, and the high-precision shallow reflection seismic profile which can clearly reflect the Quaternary geological structure is obtained, and unfavorable factors of the shallow seismic exploration data acquisition in the beach area are summarized, provides empirical advice for carrying out shallow seismic exploration in the beach area. From the shallow seismic profile, the location of the Quaternary bottom interface in the survey area is detected, and the internal layers of the Quaternary is divided, and the hidden faults in the laying range are found out. Found shallow gas in Line laying within the scope, and delineated the distribution of shallow gas along the direction of the line.