A sealant dispensing apparatus includes a rotatable injection cartridge for loading a sealant, having a plurality of outlets distributed from a periphery to a center with respect to a rotation axis of the injection cartridge; and a nozzle assembly in fluid communication with the injection cartridge, including at least two sub-nozzles arranged in a line. The outlet of the injection cartridge closer to the center of the injection cartridge is in communication with the sub-nozzle of the nozzle assembly closer to a first end of the line, and the outlet of the injection cartridge closer to the periphery of the injection cartridge is in communication with the sub-nozzle of the nozzle assembly closer to a second end of the line. The first end is opposite to the second end.