Abstract: Seismic data acquisition of marine-continental transitional zone faces both changes in water depth and the impact of some complex factors, such as sea bottom current, sea wave and outside working environment. 8L4S176T geometry is adopted for OBC seismic acquisition operation in the transitional zone of Block A on Bohai Sea. In the light of low efficiency, poor quality of geophone data, difficult to control precision of detector position and the harsh operational environment of the wave zone, a series of measures are proposed, such as shooting along the detector line, reducing the number of moving all detector-lines one time, laying and positioning the detector at the same time, laying two more cables in advance, shooting at an appropriate time, increasing the cable weight and some other appropriate methods. As a result, seismic data acquisition for the complex transitional zone in this block is successfully completed, with high-quality seismic data made available.