Yali pears (Pyrus bretschneideri Rehd.) are susceptible to mechanical damage. In this study, the protective effects of chitosan treatments on the quality of bruised pears were evaluated. The fruit were treated with 1.5% chitosan before or after bruise damage, respectively. Then, the fruit were stored at 16 °C and 85-90% relative humidity. Postharvest quality parameters were analyzed during the storage. Bruise damage accelerated the decrease of firmness and the ratio of sugar to acid, while a delay of firmness and sugar-to-acid ratio in those pears treated with chitosan before or after was found. Meanwhile, chitosan treatments both before and after damage delayed the color changes caused by damage, inhibited disease incidence increase, and enhanced the bruise recovery during the storage. Our results suggested that chitosan treatment could be used to control the physiological responses induced by bruise damage.