Abstract: A multi-component mixing injection device is provided. The device includes a mixer, an input end of the mixer is provided with two syringe barrels arranged side by side, an end of each of the syringe barrels is installed in a housing, and a handle is installed in the housing. The handle drives plungers to move towards the syringe barrels. The mixer includes a dynamic mixing tube, and a dynamic mixing structure is configured to mix different components in the dynamic mixing tube. The dynamic mixing structure includes multiple mixing blades, the multiple mixing blades are installed on a power output end of a transmission shaft, a power input end of the transmission shaft is connected to a direction conversion structure, and the direction conversion structure is connected to a power input structure through a synchronous belt. The device effectively improves the mixing efficiency through dynamic mixing.