A suction valve stem, a suction valve, an endoscopic valve kit, and a method for molding a stem are provided. The suction valve stem includes: a button head, and a stem body connecting to the button head. The stem body includes: an air passage through the center bore, a recessed slot, disposed on the stem body below the button head and above the side opening, a sealing area, disposed on the stem body below the side opening, and a flat, disposed on the stem body. The air passage includes a side opening disposed on side surface of the stem body and a bottom opening disposed at a bottom end of the stem body. The recessed slot is disposed 90 degrees from the side opening. The flat is disposed 90 degrees from the side opening and has a fluid communication to the bottom end of the stem body.