Abstract: Pyridazinone heterocyclic compounds have been exhibited good biological activity.Based on primary research,13 novel 5-acylhydrazino-3(2H)-pyridazinone compounds were designed by linking acylhydrazine with 3(2H)-pyridazinone and synthesized.All the compounds were confirmed by 1H NMR,IR and elemental analysis.The preliminary bioassay results indicated that some of the title compounds showed insecticidal activity against Aphis fabae to which the lethal rate of compound 7d was 73.9% at 500 mg/L.However,the insecticidal activity against Mythimna separata or Tetranchus urticae was not obvious.