The present invention discloses a new polyene diester and its preparation. This polyene diester has a structure of Formula 1, which is used as prodrugs by introducing diester group to polyene antibiotics, and these prodrugs exhibit antifungal or antiviral activities through releasing parent polyenes by esterase in vivo. The new derivatives have good antimicrobial activity and better safety. These new derivatives are useful for the antifungal and antiviral treatment. PA-COOR Formula 1
