To provide an injection apparatus which can be launched to inject a molten material of a plastic, metal, or the like in a short time from an optional point of time.

In the injection apparatus 10 for injection-molding the molten material M stored in the front part of the inner hole 36 of a heating cylinder 11 by pressurizing it by a plunger 14, a first driving part 30 advancing/driving the plunger 14 is set to be launched by the advancing speed of the first driving part 30 alone to push the plunger 14 after moving an idle running distance D, and a second driving part 31 is connected directly to the plunger 14.