Benzoxazines are important heterocycles bearing remarkable biological activities, which widely used in medicine, pesticide and other fields. In this study, 3-aryl-2-imino-benzo[e][1,3]-oxazin-4-ol derivatives 4a~4k were efficiently synthesized by aza-Wittig tandem reaction with simple and easy materials under mild conditions, and their structures were confirmed by ¹H NMR, ¹³C NMR and HRMS. X-Ray structure analysis of diethyl (Z)-2-((4-hydroxy-3-phenyl-3,4-dihydro-2H-benzo[e]- [1,3]oxazin-2-ylidene)amino)-5-methylfuran-3,4-dicarboxylate (4a) verified that the carbon-nitrogen (C=N) assigned Z-configuration to the compound structure. In vitro, the antitumor activities of compounds 4a~4k were analyzed with CCK8 standard method. The results indicated that most of the compounds showed potential antitumor activities. Among them, the inhibitory rate of the most active compound diethyl (Z)-2-((4-hydroxy-6-methyl-3-phenyl-3,4-dihydro-2H-benzo[e][1,3]oxa- zin-2-ylidene)amino)-5-methyl-furan-3,4-dicarboxylate (4e) against HepG2 and HeLa cell lines at the concentration of 0.01 mg/mL were 45.83% and 42.76%, respectively, which were weaker than the commercial gefitinib. Furthermore, their antioxidant properties were detected via 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. The results showed that the IC₅₀ values of free radical scavenging rates of diethyl (Z)-2-((4-hydroxy-3-phenyl-3,4-dihydro-2H-benzo[e][1,3]oxazin- 2-ylidene)amino)-5-methylfuran-3,4-dicarboxylate (4d), 4e and diethyl (Z)-2-((6,8-dichloro-4-hydroxy-3-phenyl-3,4-dihydro- 2H-benzo[e][1,3]oxazin-2-ylidene)amino)-5-methylfuran-3,4-dicarboxylate (4j) were 0.294, 0.255 and 0.338 mmol/L, respectively, which slightly higher than that of the control ascorbic acid.