The practices of the exploration and development of shale gas in the Sichuan Basin in recent years show that deep⁃water shelf facies and good preservation conditions are key factors for shale gas'enrichment and high yields. Meantime, the drilling results of shale gas wells targeting the upper Paleozoic marine shale indicate a phenomenon that high production wells have abnormal high pressure, while low gas production wells have normal to low pressure. Shale gas' production and pressure coefficient show positive correlation. Based on qualitative assessments of shale gas, many researchers concluded that areas where shales are buried moderately, covered and bedded by proper rocks, and are far away from large open faults, uplifts, or erosion areas, as well as the places where there exists short period of tectonic movements and good structural patterns are the places that possess good preserving conditions. Based on the drilling data of marine⁃shale wells within southeastern Sichuan Basin, the authors revised the Fillippone formula and generated a new formula for predicting pressure coefficient which fits better to this region. With DS area as an example, this paper illustrates the prediction of the pressure coefficient of the Wufeng⁃longamxi Formation through a high⁃resolution inversion, and the result turns out to be good.%近年来页岩气勘探开发的实践表明，深水陆棚有利相带及良好的保存条件是页岩气高产富集的关键，而压力系数是保存条件的综合判别指标，页岩气产量与压力系数呈现出明显正相关关系，因而压力系数的预测及研究对页岩气勘探获得成功至关重要。以近年来川东南海相页岩气探井为基础，其至上而下钻遇地层复杂，同时难以建立准确的正常压实曲线，认为传统的Fillippone公式、等效深度法、Eaton及有效应力法等压力预测方法均不适用于本区，通过对Fillippone公式的改进，总结出了适用于川东南海相泥页岩地层的压力系数预测公式，并应用于川东南丁山地区。以丁山三维地震资料为基础，在高精度速度建模及反演的基础上完成了丁山地区志留系龙马溪组泥页岩地层的压力系数预测，取得了良好的效果。预测结果表明：丁山地区压力系数变化较为明显，由盆缘到盆内压力系数不断增大，页岩气保存条件较为复杂。
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