Abstract: From 1990 to 1997, Zhujiangkou Basin's oil output had increased rapidly, leading to rapid increase of China offshore oil production. But since 1997, production of this basin declined quickly, this has remarkably low ed the grow th of China offshore petroleum output. Since 1990, about 82.5%of annual output average increases of China come from offshore area. So in the future, we must use Bohai Basin increased output minus Zhujiangkou Basin decreased output to calculate the grow th of China offshore output. Frontier exploration of China offshore is not clear, but in the world, offshore petroleum will take more and more important shares, deepwater exploration and production will become a new hot point. We should not only see deepwater exploration as a chance to break passive phases of the South Sea exploration, but also participate into the international offshore market all-round.