Fine description and comparative study of the geochemical features of source rocks in the Nanpu Sag of the Bohai Bay Basin have been made according to multiple parameters. It has been concluded that effective source rocks in the 3rd member of the Shahejie Formation are regarded as excellent effective hydrocarbon source rocks thanks to big thickness and high organic abundance (2. 5% -8% ). They are mainly of II, and I organic types, and are in mature and over mature stages. Effective source rocks in the 1 st member of the Shahejie Formation are regarded as good ones since the organic abundance ranges from 1. 2% to 2. 3% , and the organic types are dominated by II2 and El. Effective source rocks in the 3rd member of the Dongying Formation are regarded as relatively good ones of mature stage since the organic abundance ranges from 0. 2% to 2.6% , and the organic type is dominated by II2. 3 regions favorable for exploration in the Nanpu Sag have been pointed out. 1) Structures Nanpul-2 and 3-4 close to hydrocarbon generation sags dominated by types II, and I source rocks. 2) Structures Gaoshangpu and Liuzan close to hydrocarbon generation sags dominated by types II2 and I source rocks. 3) Structures Laoyemiao - Beipu and Nanpu5 close to hydrocarbon generation sags dominated by types II2 and HI source rocks.%通过对渤海湾盆地南堡凹陷烃源岩地球化学特征的多参数精细描述和对比研究认为,沙三段有效烃源岩厚度大,有机碳含量高达2.5％～8％,以Ⅱ1和Ⅰ型有机质为主,处于成熟—高成熟阶段,为好的有效烃源岩；沙一段有机碳含量1.2％ ～2.3％,有机质类型以Ⅱ2和Ⅲ型为主,为好的有效烃源岩.东三段有机碳含量0.2％ ～2.6％,以Ⅱ2型有机质为主,处于成熟演化阶段,为较好的有效烃源岩.因此,预测南堡凹陷勘探有利方向:第一类为紧邻以Ⅱ1和Ⅰ型有机质烃源岩为主的生烃凹陷分布的南堡1-2号构造和南堡3-4号构造；第二类为紧邻以Ⅱ2和Ⅰ型有机质烃源岩为主的生烃凹陷分布的高尚堡构造—柳赞构造；第三类是紧邻以Ⅱ2和Ⅲ型有机质烃源岩为主的生烃凹陷分布的老爷庙构造—北堡构造和南堡5号构造.
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