Based on the test results from 62 groups of groundwater samples in the central Dingjing area in the northern region of Shannxi Province in the year 2013, the single factor index evaluation method, the Nemerow index evaluation method, the hierarchical evaluation method, and the fuzzy comprehensive evaluation method were used to evaluate the quality of groundwater in the study area. Comprehensive weighted averaging of the evaluated results was carried out in order to obtain results that were ultimately reliable, providing a basis for the rational development and protection of the groundwater resources in this area. The evaluation results show that groundwater of grades I, II, III, IV, and V accounted for 3. 23%, 11. 29%, 9. 68%, 24. 19%, and 51. 61%, respectively, and about 75% of groundwater was not suitable for drinking. The overall quality of groundwater was poor in the study area. The groundwater quality was good in the northeastern desert-plain area and poor in the southwestern loess hilly area. In addition, the groundwater quality was poor in the densely-mined oil and gas well areas and around the Luhe River, indicating that the primitive environment and human activities are two main factors of poor quality of groundwater.