Methods of dissolution in water with different temperature and N leaching from soil were used to study the relationship between amount of N release from coated urea and film thickness,temperature affect on film stability.Results showed that the amount of N release from coated urea reduced with film thickness increasement.Rate of N release from coated urea was too quicker with only net film material coated to slow N release.The method of 2% stem material permeate thorough film could slower N release effectively,the period of N release time was over 70 d in 30℃ water.Character of film material was water resistant and extrusion.Affect of temperature on film stability was not significant below 30℃,and was significant over 45℃.