A device for preparing a sucrose-6-ester, comprising a tank body, a heating pipe, an annular cooling apparatus, and a motor, wherein the annular cooling apparatus and the heating pipe are arranged in the tank body sequentially from inside to outside in a nested manner; the annular cooling apparatus comprises a condensation inner wall, a condenser pipe, and a condensation outer wall that are arranged sequentially from inside to outside in a nested manner; a distillation chamber is formed between the heating pipe and the tank body, a condensation chamber is formed between the heating pipe and the condensation outer wall, and a hollow portion of the condensation inner wall forms a reaction chamber; the motor electrically connects the heating pipe and the condensation inner wall, and is able to drive the heating pipe and the condensation inner wall to rotate; a feed inlet is configured at one end face of the tank body, and at such end face, configured also are a product discharge pipe connected to the reaction chamber and a condensated water outlet pipe connected to the condensation chamber; the other end face of the tank body away from the feed inlet is provided with a carboxylate feed pipe connected to the reaction chamber; the feed inlet, the product discharge pipe, the condensated water outlet pipe, and the carboxylate feed pipe penetrate through end faces of the tank body, respectively; the heating pipe is provided with a vapor outlet such that a water vapor is able to enter the condensation chamber from the distillation chamber; and an evaporation residue channel is fixed at an end of the heating pipe away from the feed inlet, and the evaporation residue channel does not contact the annular cooling apparatus and communicates with the reaction chamber. the annular cooling apparatus and the heating pipe are arranged in the tank body sequentially from inside to outside in a nested manner; the annular cooling apparatus comprises a condensation inner wall, a condenser pipe, and a condensation outer wall that are arranged sequentially from inside to outside in a nested manner; a distillation chamber is formed between the heating pipe and the tank body, a condensation chamber is formed between the heating pipe and the condensation outer wall, and a hollow portion of the condensation inner wall forms a reaction chamber; the motor electrically connects the heating pipe and the condensation inner wall, and is able to drive the heating pipe and the condensation inner wall to rotate; a feed inlet is configured at one end face of the tank body, and at such end face, configured also are a product discharge pipe connected to the reaction chamber and a condensated water outlet pipe connected to the condensation chamber; the other end face of the tank body away from the feed inlet is provided with a carboxylate feed pipe connected to the reaction chamber; the feed inlet, the product discharge pipe, the condensated water outlet pipe, and the carboxylate feed pipe penetrate through end faces of the tank body, respectively; the heating pipe is provided with a vapor outlet such that a water vapor is able to enter the condensation chamber from the distillation chamber; and an evaporation residue channel is fixed at an end of the heating pipe away from the feed inlet, and the evaporation residue channel does not contact the annular cooling apparatus and communicates with the reaction chamber.