文中介绍了川西浅气层钻白浅 2 9井实施欠平衡钻进的方法 ,认识到欠平衡钻井具有发现油气层、减少对油气层伤害、提高钻速、避免漏失、减少粘附卡钻等优点 ,在川西浅气层勘探开发中有广阔的前景。同时也分析了欠平衡钻井应注意地层是否适合 ,钻井液的选择及安全问题 The paper introduced the method of underbalanced drilling in the Shallow shallow 29 wells in the shallow layer of western Sichuan, and realized that the underbalanced drilling has the ability of discovering the oil and gas layers, reducing the damage to the oil and gas layers, increasing the drilling speed, avoiding the loss, reducing the stuck stuck drill Advantages, in the western Sichuan exploration and development has a broad prospect. At the same time, it is also analyzed that underbalanced drilling should pay attention to the suitability of formation, selection of drilling fluid and safety issues