A series of novel 12-(aryloxyacyloxyimino)-1,15-pentadecanlactone derivatives (3) were synthesized, and their structures including configuration of C=N bond were confirmed by (1)H NMR, elemental analysis and X-ray diffraction analysis. The bioassay showed that some of them exhibited excellent herbicidal activity against Amaranthus tricolor L. The activity of compounds 3 except compounds 3A1-2 was much higher than the commercial herbicide 2,4-D and the activity of about half of compounds 3 was comparable to the commercial herbicide tribenuron-methyl. The further bioassay showed that the representative of compounds 3, 3A1-12, exhibited excellent herbicidal activity not only against dicotyledon, such as Amaranthus tricolor L., Cucumis sativus L., Glycine max L., and Phaseolus radiatus L., but also against monocotyledon, such as Zea mays L. and Oryza sativa L.