Based on outcrops observation and samples test on black shale from lower Cambrian in northwest Hunan, the parameters such as distribution of black shale, lithologic character, organic matter type, organic carbon content, shale maturity, mineral characteristics of reservoir and characteristics of shale gas caprocks were evaluated. The geologic analogy method was applied to evaluate geological parameters in the studied area. The results show that the shale in this area has large thickness, distribution stability, high content of organic carbon, high maturity, high contents of brittle minerals, good reservoiring and capping conditions, and it is dominated byⅠandⅡ1 type organic matter. The shale in the studied area is similar to Barnett shale in Vossburg Base. The geological risk score from Niutitang Formation of lower Cambrian is 0.052. The shale gas resource of shale from Niutitang Formation of lower Cambrian is (2.54−3.38)×1012m3 by specific calculation. Wentang—Dayong—Cili is the target zone of shale gas, while Huayuan—Baojing—Yongshun and Ciyantang of Longshan are the favorable exploration area. The south wing of Sangzhi—Shimen synclinorium is regarded as the prospect area.%在对湘西北地区下寒武统牛蹄塘组黑色页岩露头观察和取样分析基础上，对黑色页岩的平面展布、岩性特征、有机质类型、有机碳质量分数、页岩成熟度、储层矿物特征、页岩气储盖特征等参数进行评价。应用地质类比法评价研究区的各地质参数。研究结果表明：区内页岩厚度大，平面分布稳定，有机质类型以Ⅰ和Ⅱ1型为主，有机碳质量分数高，成熟度高，脆性矿物丰富，储盖条件较好；研究区与沃斯堡盆地 Barnett 页岩较相似；评价区下寒武统牛蹄塘组黑色页岩的评价参数的地质风险得分为0.052，下寒武统牛蹄塘组页岩气地质资源量为(2.54~3.38)×1012 m3；温塘—大庸—慈利一带为页岩气勘探目标区，花垣—保靖—永顺及龙山茨岩塘一带为勘探有利区，桑植—石门复向斜南翼为勘探远景区。
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