The invention discloses a reciprocating sealing device for studying the influence of piston rod eccentricity on the performance of a sealing element. The reciprocating sealing device comprises a sealing element test system, an eccentric adjustment system, a left reciprocating drive system, a right reciprocating drive system, a hydraulic pump station and a base, wherein the sealing element test system comprises a piston rod, tension and pressure sensors connected to the left and right ends of the piston rod respectively, a cylinder tube, a left end cover, a right end cover and the bolts, the cylinder tube is connected with the left end cover and the right end cover by the bolts, the left and right end covers are provided with mounting seats, static sealing elements, sealing elements to be tested and guide rings, and the left and right tension and pressure sensors are connected with the left and right reciprocating drive systems respectively and used to measure the friction force of theleft and right sealing elements to be tested respectively; the eccentric adjustment system comprises a support plate, a front bracket, a rear bracket and eight screw micrometers distributed on the four corners of each of the front and rear brackets up and down. Through the fine adjustment of the screw micrometers, the left and right non-horizontal adjustment and the front and rear angular deflection adjustment of the support plate can be realized, so that the eccentricity of the piston rod is inconsistent with the circumferential compression ratio of the sealing elements to be tested.