Abstract: This paper illustrates the experiences in successful exploitation of gas/oil fields at home and abroad, simultaneously analyses the lessons of different economic benefit obtained from exploiting fields causing by incomplete plans and unharmonious link from upstream to downstream.Moreover, facing the situation that during the last 20 years of exploration on the Shelf Basin of the East China Sea, 8 gas/oil fields like Pinghu, Chunxiao and a group of gas/oil bearing structures have been founded by Shanghai Offshore Petroleum Bureau, this paper proposes to pay enough attention to the economic benefit of exploitation, and to obtain, when getting good social influence, the best economic benefit as well.Last the paper presents the suggestions proposed by specialists of setting up sound laws and regulations on the exploitation of gas/oil fields and the utilization of downstream.