Solvent impregnated resins (SIR) with di (2,4,4 trimethylpentyl)phosphinic acid (Cyanex 571) were studied by adsorption of the extractant into Amberlite XAD 4; XAD 7; XAD 1180 polymeric adsorbents. The results shas that Cyanex 571/XAD 7 impregnated resins containing extractant of 0 35～0 45 g·g -1 resin have a favorable extractive activity in HCl medium. The rare earths (Tb 3+ , Dy 3+ , Ho 3+ , Er 3+ ) are separated by using SIR as the column stationary phase. The better separation effect is obtained at lower load and slower elution rate. Solvent impregnated resins (SIR) with di (2,4,4 trimethylpentyl) phosphinic acid (Cyanex 571) were studied by adsorption of the extractant into Amberlite XAD 4; XAD 7; XAD 1180 polymeric adsorbents. The results shas that Cyanex 571 / XAD The rare earths (Tb 3+, Dy 3+, Ho 3+, Er 3+) are separated by using 35 to 0 45 g · g -1 resin with a particularly extractive activity in HCl medium SIR as the column stationary phase. The better separation effect is obtained at lower load and slower elution rate.