Herein, we present that treating N-(2-oxo-2-phenylethyl) substituted 2-pyridones with styrenes in DMSO/H2O at 120 °C affords 1,6-carboannulated 2-pyridone scaffolds with up to 79% yield. This protocol provides a simple and efficient method for obtaining complicated bicyclic 2-pyridones through a radical cascade reaction. Additionally, we have successfully synthesized 27 target compounds, which confirms the practicality and wide applicability of the proposed reaction.