The sugar cooking liquid from the process of preserved cherry tomato can not be used again due to its high viscosity after multiple rounds of sugar infiltration. In order to provide a theoretical basis for the viscosity reduction process of the sugar cooking liquid， this paper analyzed the physical/ chemical and rheological properties of the sugar cooking liquid， and studied on the influence of pectin and pulp in the sugar cooking liquid on the rheological properties of the sugar cooking liquid. The results showed that the original and usable sugar cooking liquid had shear thinning behavior， which were non-Newtonian fluids. The content of soluble pectin in the serum of sugar cooking liquid was 0.005‰-0.009‰， the pectin content was very low， and the viscosity could be reduced by up to 2% after pectinase treatment， which was not the main reason for high viscosity of sugar cooking liquid. However， the pulp in the sugar cooking liquid had a significant impact on the rheology of the sugar cooking liquid. After the pulp was removed， the viscosity of the original and usable sugar cooking liquid were reduced by 33% and 58% respectively， and they showed the characteristics of Newtonian fluid， which was the main reason for the high viscosity of the sugar cooking liquid. It was found that the aqueous extracts such as pectin and protein had an important influence on the rheological properties of the sugar cooking liquid. The contribution of the pulp to the viscosity of the sugar cooking liquid was reduced by about 50% after the aqueous extract was removed. The aqueous extract such as pectin and protein may play an important role in the interaction between the soluble substances in the sugar cooking liquid and the pulp to form a dense network.