In this study, the effects of enzymes on wool yarn in the presence of different salts (ammonium sulfate, sodium tetraborate, and di-sodium hydrogen phosphate) were investigated. Alcalase 2,5 LDX and Savinase 16 LEX were selected as proteolytic enzymes. In addition, the effects of surfactants (Sandozin NRW, Irgasol NA, Erkantol NR, and Sandozin EH) on the enzyme treatment of wool yarn were evaluated. The results indicated that the effects of enzymes on wool yarn were greatest in the presence of sodium tetraborate. Furthermore, the properties of wool yarn such as weight loss, strength loss, and hairiness were influenced by these surfactants. The SEM images of the treated samples confirmed the obtained results.