A series of N,N'-diacylhydrazines were prepared and their structures were confirmed by 1H NMR, MS and FTICR-MS. They were tested radical-scavenging activity in vitro. The preliminary bioassays of title compounds showed that two compounds had excellent radical-scavenging activity comparable with vitamin C, while the activity is highly relative to the substituents. Surprisingly, several compounds also exhibit favorable fungicidal activities. To further explore the comprehensive structure-activity relationships about the fungicidal activity, a three-dimensional quantitative structure-activity relationship analysis using the method of comparative molecular field analysis was performed.