Base‐promoted formal [4+2] cycloaddition reaction of (Z)‐2‐(2‐hydroxy‐2‐alkylvinyl)quinoline‐3‐carbaldehydes and allenoates represents an efficient method for the synthesis of functionalized acridines through a sequential Michael addition, aldol condensation, and isomerization process in a mild condition. This new approach tolerates a wide range of (Z)‐2‐(2‐hydroxy‐2‐alkylvinyl)quinoline‐3‐carbaldehydes and allenoates and affords the functionalized acridines in good to excellent yields. The exclusive selectivity, high atom economy, and high bond‐formation efficiency of this method makes it a valuable approach for the synthesis of acridine backbones.