As the double core of the Beijing-Tianjin metropolitan area, Beijing and Tianjin play an important role in driving the development of the whole region. However, the regional environmental problems, such as water degradation, air pollution, and land deterioration, are becoming more and more critical. Clarifying the relationship of the development and distribution of cities with regional water degradation pattern will supply theoretical bases to regional eco-environmental risk management, which is profound both for controlling the pollution of Beijing-Tianjin area from the origin and for the urbanization preference of other regions. The water shortage and pollution problems initiated by urbanization are the hot spot issues concerned in economic and environmental fields. Most of the relative researches reflect the degree of urbanization through defining urban, urban fringe and suburb. However, the division is inevitably subjective, and cannot clarify the relationship between environmental quality and urbanization level. Hence, this paper quantitatively analyzes the urbanization impacts on water quality and landscape pattern in Beijing-Tianjin metropolitan area by utilizing several models, from different angles and scale, based on GIS. The results show that: 1. The spatial distribution of river pollution in Beijing-Tianjin area has significant spatial autocorrelation and patchiness. The integrated pollution indexes in the cities of every districts and counties are greater than the indexes in the surround areas, which mean that pollution in cities is worse than in surround areas and river pollution is closely related to human activity. 2. Economic development potential field model is used to characterize human activity intensity. The analysis shows that the economic development situation can be perfectly simulated by the model. It is found by regression analysis that river water quality first degrades and then increases along with economic development potential field force. 3. The relationships between development potential index, landscape pattern characteristics and integrated pollution index are analyzed by and regression analysis，based on GIS. It is found that there is apparent correlation between landscape indexes and development potential which is mostly affected by the intensity of roads. The result shows that the relationship between river pollution and development potential is complex, but is affected by fixed assets investment proportion, industrial structure and the industrial gradient to central city. Landscape and water quality can be forecasted by economic activity, to some extent. 4. At the sub-watershed scale, TN, TP, and NH4-N are affected by economic development level and population density, while COD is affected by industry structure and scale. Hence, the emission decrease measures should be enacted specifically. The areas with high COD should adjust industry structure to decrease industry pollution. The areas with high TN, TP, and NH4-N should make effort to treat sanitary sewage and decrease sanitary sewage resources. 5. The relationship between social economic status and water quality in districts and counties is studied from environmental justice. The result shows that the main affecting factors of environmental justice are industry structure and scale in Beijing-Tianjin area. It is critical to regulate industry structure to reduce environmental risks.