The invention discloses a downhole multistage separation rod pump same-well production and injection method and pipe column. The downhole multistage separation rod pump same-well production and injection pipe column comprises a same-well production and injection pump, a selective material separation device, a hydraulic cyclone separation device and a gravity separation device, wherein the selective material separation device, the hydraulic cyclone separation device and the gravity separation device are connected in arbitrary sequence, and the lower end of the same-well production and injectionpump is connected with the separation device on the uppermost portion. The same-well production and injection pump comprises a pump cylinder and a plunger inside the pump cylinder; the upper end of the plunger is connected with a sucker rod; the upper end of the pump cylinder is connected with an oil production pipe; and a production channel is formed by the oil production pipe. The lower end ofthe gravity separation device is connected with a reinjection pipe; a reinjection channel is formed by the reinjection pipe; and a side inlet valve is arranged on the side wall of the upper end of thereinjection pipe, and a reinjection valve is arranged at the lower end of the reinjection pipe. According to the downhole multistage separation rod pump same-well production and injection method andpipe column, multiple separation technologies of downhole selective material oil-water separation, hydraulic cyclone separation, the gravity separation and the like are integrated; and efficient downhole oil-water separation of production liquid is achieved, and the purposes of same-well production and injection, water content reduction and oil-production stabilization are achieved.