A pump arrangement, in particular a magnetic clutch pump arrangement, is provided. The pump arrangement includes a pump housing containing an impeller shaft, an impeller, a casing cover adjacent to the impeller and supporting a plain bearing arrangement. The pump arrangement also includes a containment shell which seals an enclosed chamber within the inner chamber of the pump housing. The plain bearing arrangement includes first and second bearing sleeves connected to the impeller shaft, a first bearing bush which cooperates with the first bearing sleeve via a radial bearing surface and is connected to the pump housing or to a component secured to the pump housing a second bearing bush which cooperates with the second bearing sleeve via a radial bearing surface and is connected to the pump housing or to a component secured to the pump housing, and a retainer ring mounted between the first and second bearing sleeves. The retainer ring has, in the end surface facing the first bearing bush a first annular groove which receives a first axial bearing ring, and in the end surface facing the second bearing bush a second annular groove which receives a second axial bearing ring.