Nowadays, using sustainable dyeing process has become a necessity, but does not meet performance requirements. Application of biomordants was recommended to enhance the quality of dyeing. Tannin-based biomordants appearedadvantageous in green dyeing; meanwhile, unconditional affinity towards fibers of different types has attracted the attentionof researchers. We introduce the idea of using combination of natural mordant as a new technique for sustainable dyeing ofwool and a model natural fiber. In this study, Iranian madder was used as green dye and Yellow Myrobalan (YM) and BlackMyrobalan (BM) employed as biomordant. FTIR-ATR spectra of the washed, mordanted, and mordanted-dyed wool fibersconfirmed appropriate bonding among wool fibers, green mordant, and dye molecules. The superior color strength of woolfibers dyed with 4 %YM+6 %BM and 40 % madder was featured by K/S value of 35.77 and was obviously higher than thatof madder by sumac, 9.5. Fastness properties (light, wash, and rub fastness) of wool dyed with combination of YM and BMwere good.