The digestion regularity of MCPA,ametryn and diuron which were the active ingredients of 55% MCPA·ametryn·diuron WP in sugarcane leaves and soil of sugarcane plantation collected from Changsha of Hunan Province and Haikou of Hainan Province in 2009 and 2010were studied in the paper,and the results showed that these three agents had rapid digestion. The final residue test showed that both MCPA and ametryn had not been detected in the study; the average residues of diuron in the soil collected from Hunan Province in 2009 and 2010 were 0. 018 and 0. 015 mg / kg,respectively which were slightly larger than the critical value of 0. 013mg / kg; diuron had no been detected in other treatments. The digestion regularity of MCPA, ametryn and diuron which were the active ingredients of 55% MCPA · ametryn · diuron WP in sugarcane leaves and soil of sugarcane plantation collected from Changsha of Hunan Province and Haikou of Hainan Province in 2009 and 2010were studied in the paper , and the results showed that those three agents had rapid digestion. The final residue test showed that both MCPA and ametryn had not been detected in the study; the average residues of diuron in the soil collected from Hunan Province in 2009 and 2010 were 0. 018 and 0. 015 mg / kg, respectively which were slightly larger than the critical value of 0. 013 mg / kg; diuron had no been detected in other treatments.