An injection-molding system includes an extruding system configured to produce a mixture; discharging channels communicable with the extruding system, wherein each of the discharging channels includes an outlet; and a molding device configured to receive the mixture from the outlets and including a space and feeding ports correspondingly engageable with the outlets. An injection-molding method includes providing an extruding system configured to produce a mixture, a first discharging channel including a first outlet, a second discharging channel including a second outlet, and a molding device including a space and first and second feeding ports communicable with the space and respectively engageable with the first and second outlets; engaging the first outlet with the first feeding port; engaging the second outlet with the second feeding port; injecting the mixture through the first outlet and the first feeding port; and injecting the mixture through the second outlet and the second feeding port.