The work aims to study the causes of clatter and locking in the food extrusion process of twin-screw extruder, and to provide theoretical guidance for the design and application of twin-screw extruder. ABAQUS software was used to construct the simulation model of the twin-screw extruder. The temperature load was set according to the temperature feedback from the sensor. At the same time, the pressure load was set under the low pressure condition, normal condition and limit condition of the twin-screw extruder. The temperature distribution, stress and deformation of the cylinder were simulated and analyzed by the thermo-mechanical coupling theory. Under the maximum temperature condition, the axial thermal deformation of the cylinder was 2.356 mm, the total thermal deformation was 2.358 mm, the thermal deformation in the x direction was 0.1324 mm, and the thermal deformation in the y direction was 0.1592 mm. Under the coupling effect of maximum temperature condition and ultimate pressure, the total deformation of the barrel was 2.088 mm. The thermal expansion caused by temperature was the main reason for the deformation of the cylinder, and the axial thermal deformation of the cylinder was equivalent to the total thermal deformation, and was much larger than that of the other two directions. Compared with the normal temperature environment, the deformation of the cylinder decreased with the increase of pressure under the condition of heating temperature. The effects of temperature on the performance of the extruder should be considered and reasonable temperature parameters should be set in application.