Despite its critical role in regulating the global climate and carbon cycle, the evolution of Pacific abyssal circulation has not been fully deciphered during the last glacial cycle. Using the oxygenation and benthic δ13C gradient records, tracers that are sensitive to ocean circulation rates, we establish the abyssal Pacific overturning conditions since ~90 ka. Our results indicate that the intensity of abyssal Pacific overturning is closely related to atmospheric CO2, with accelerated overturning during steps of CO2 rise. Those depict a potential pathway of deep carbon dioxide into the atmosphere and highlight the critical roles of deep Pacific circulation in the global carbon cycle.