Application of using rare earth salts with acid dyes for dyeing wool fabrics have been investigated. The rare earth salts used include neodymium chloride, samarium oxide and gadolinium oxide; and acid dyes used are C.I. Acid Red 114, C.I. Acid Yellow 42 and C.I. Acid Blue 113. The results of these experiments exhibit that the addition of rare earth salts does lower the dyeing temperature of wool slightly, and the addition of neodymium chloride achieved the better result. The result of mixing different rare earth salts is not very distinct, although the mixture of neodymium chloride and gadolinium oxide in the ratio 8:2 has the best effect. Moreover, the addition of rare earth salts has no great impact on the tenacity of dyed fabrics. Among the color range of dyed fabrics, Red 114 has better color strength. Furthermore, the washing fastness of fabrics can be up to grade 4-5 in general, while its dry rubbing fastness can be up to grade 4-5 and its wet rubbing fastness can be up to grade 3-4.