Based on the theory of organizational penalty spillover, this paper discusses whether the punishment against interlocking company will affect the accounting information quality of the observing company through the channel of interlocking directors. The research results show that the observing company significantly improves the accounting information comparability within two years after interlocking company is punished when compared horizontally with an interlocking company that is not punished. The observing company also significantly improve the accounting information comparability within two years after the interlocking company is punished when compared longitudinally with before an interlocking company is punished. The findings show that the punishment against listed companies by CSRC and other regulatory authorities have spillover effect, the punishment is not only an act of correcting deviations after the event, but also an attempt to improve the accounting information quality of unpunished companies by punishment that is a Warning to Others.