A pharmaceutical syringe unit is configured to be mounted to a pharmaceutical injection device main body and hold a pharmaceutical-filled pharmaceutical syringe, in order to mount the pharmaceutical syringe to a pharmaceutical injection device, wherein a syringe cover is configured to slide forward and backward with respect to a distal end cap by operation of the pharmaceutical injection device main body, thereby allowing movement between a needle insertion position at which insertion of an injection needle into a target is to be completed, and a needle withdrawal position at which withdrawal of the injection needle from the target is to be completed, and a guide component is configured to guide the syringe cover over a range that is greater than a distance between the needle insertion position and the needle withdrawal position.