Abstract: Aqueous solution of 20% Difenoconazole Microemulsion was used to control Pear Scab in Field. The results showed that the control effect of the solution diluting 8000 times of 20% Difenoconazole Microemulsion was better than the 10000 times dilutions and the 12000 times dilutions. The effect was up to 98%. It was safe compared with CG and it could be recognized the ideal pesticide against the Pear Scab.