With the advantages of high efficiency and low cost, the single-channel marine reflection seismic survey has broad application prospects in the field of offshore engineering geophysical exploration. Based on a description of its basic principle, this paper deals with the method for suppressing the interference of multiple wave and noise under the condition of offshore shallow water and, exemplified by some typical cases in Hong Kong, recounts some related marine seismic techniques such as data acquisition, data processing and data interpretation.