[Objective] The ecological condition in the Niulan River was investigated to provide bases for ecological management and restoration project. [Methods] Based on the investigation of water quality, riparian zone and pollution sources of the study reach, a comprehensive evaluation method was used to evaluate the survey data. [Results] The natural condition of Kraal River is good. Of which, reaches of 8-10 are in the state of nature, 3, 5-7 reaches are in near natural state, 1, 2, 3 reaches are in a degraded natural condition. The water quality of Kraal River is general poor. If river harnessing being continued, the water quality would improve from downstream to upstream gradually. [Conclusion] The main pollution sources of the study reach are manure, garbage pollution and sewage pollution. Therefore, in the future governance, these pollution should be focused.