Natural dyes have become an alternative option of interest for textile dyeing. The selection of native species as a natural dye can make its use feasible and enhance local biodiversity. In the present study, the extract of Croton urucurana Baill. bark, which is native to Brazil, was investigated as a natural textile dye. The extract showed a reddish-brown color and the presence of tannins. The extract was characterized by physicochemical methods and optimization of the dyeing process was determined by factorial design 23. The dyed fabrics were evaluated for color fastness to light, wash, rubbing and perspiration. They showed colors between beige and reddish-brown and had good fastness properties. Antibacterial activity assessment was performed on the extract and fabrics and UV protection was evaluated in the fabrics. The wastewater generated from the dyeing process was also characterized. It exhibited high biochemical oxygen demand and chemical oxygen demand, in addition to a large amount of dissolved iron and aluminum, when these metals were used as a mordant in the dyeing process. On balance, the extract of C. urucurana has the potential to be employed as a textile dye. •Analysis of C. urucurana bark extract showed the presence of tannin-based colorants.•C. urucurana bark extract was used to dye cotton and wool in beige to reddish brown shades.•The 2³-statistical experimental design method gave the optimized dyeing method.•Wastewater analysis indicated that treatment is needed before effluent releases.