The present invention relates to a non-contact continuous type sensing device for a flowmeter and a sensing method thereof. The flowmeter includes a movable member that is connected to an operating member and that is driven by a fluid to move, thereby moving the operating member. A projector is mounted above the operating member and projects signals onto the operating member. At least two regions are defined in a side of the operating member facing the projector. At least one of the at least two regions includes metal material to reflect the signals projected thereon. A signal density in a space between the projector and the operating member is changed when the operating member is passing through the space, such that the projection power of the projector is affected to thereby sense a movement condition of the operating member and to thereby continuously know a flowing condition of the fluid.