1,3,5-tri-substituted benzene rings emerged with unique properties has widespread applications in materials, boosting the rapid development of their synthesis. Despite the significance, the direct construction of hetero-1,3,5trisubstituted benzene core was far less-developed. Herein, we realized a DBU-mediated isomerization/6-π electro-cycliza-tion/oxidative aromatization cascade of sulfonyl-substituted allenyl ketones under an air atmosphere (DBU = 1,8diazabicyclo[5.4.0]undec-7-ene). This versatile protocol featured metal-free conditions, easy operation, and broad functional group tolerance provides a new avenue for the construction of hetero-1,3,5-tri-substituted benzene.