This paper describes kinetic studies on, and the identification of products from, the ozonolysis in aqueous solution of the cellulose model compounds methyl LY- D -glucopyranoside, methyl p-D-glucopyranoside, and anhydrocellobiitol. The purpose of these studies was to understand more clearly the processes involved in the degradation of pulp carbohydrates by ozone, a potential but little used pulp bleaching agent. The kinetics of the ozonolysis showed that the P-glucoside reacted 1.8 times as fast as the a-glucoside under the same conditions. The rate was dependent on initial concentration of substrate showing the importance of the diffusion rate of ozone in water. Product analysis showed that anhydrocellobiitol on ozonolysis yielded gluconolactone, glucose and anhydroglucitol as primary products, indicating that ozonolysis caused both oxidative and hydrolytic cleavage of the glycosidic bond. These results clearly demonstrate how very susceptible pulp carbohydrates are to oxidative and hydrolytic degradation by ozone, the p-1 : 4 linked glucosides being much more susceptible to cleavage than the a-1 : 4 linked glucoside.