Abstract: In Bohai sea area, offshore drilling is less, oil and gas exploration and development is in high level of dependence on seismic data. By using seismic amplitude, abundant achievement has been made on lithology identification and fluid detection. Because of many influence factors of seismic amplitude, if not fully studying and understanding these factors, oil & gas exploration and development may fall into the trap by using seismic amplitude information, causing some well lost. In order to avoid the traps caused by seismic amplitude, various factors effecting seismic amplitude are discussed from many aspects as seismic data acquisition, processing and geology, which has practical significance on lithology identification, fluid detection and well exploration success rate.