Abstract: In view of influencing factors of oil production rate, the production performance data collected from130mid?high permeability clastic rock oilfields at home and abroad are analyzed, among which the most oilfields are developed by water injection process. In terms of crude oil viscosity and reservoir permeability, the oilfields were divided into six types such as low viscosity and high permeability, low viscosity and medium permeability, medium viscosity and medium permeability, medium viscosity and high permeability, medium viscosity and extra?high permeability, and mid?high viscosity and extra?high permeability oilfields. For these different oilfields, the influencing factors of crude oil viscosity, reservoir permeability, reserves abundance, well spacing density, injector?producer ratio on the oil production rate were analyzed. The results indicate that the oil production rate at early stage of water injection development is mainly influenced by the oil viscosity, reserves abundance and reservoir permeability rather than that at late stage of it; the oil production rate at mid?late stage is mainly influenced by well spacing density and injector?producer ratio, the factors have little influence on that at early stage