Objective:To isolate virulent bacteriophage from environment samples and explore the potential way of decontaminating the environmental wastewater. Methods: The standard plaque assay

negative staining transmission electron microscopy （TEM）

genome extraction and nucleases test were used to isolate bacteriophages. Then its morphology and characteristics were examined. Results: A novel bacteriophage XY-1 was isolated from a sewage pond in a hospital. It infected and killed 6 E.coli reference strains. The phage had a round head （diameter 40-50 nm）

no tail and the genome was ssRNA of approximately 5.0 kb. It was able to reduce E.coli to an extent of 44.63% to 67.00% when being added into the samples of different raw sewage water

depending on the contact time

the temperature and the phage dose. Conclusion: From the morphology typical and nucleotide characteristics （RNA） of the genome of phage

phage XY-1 appears to be closely related to phage f2. It may have some effects for the control of E.coli in sewage water.