Removal of dyes colour and Cu(II) metal ion from aqueous solution using acetone-formaldehyde-salicyclic acid (AFSA) resin has been carried out. The results revealed that AFSA resin acts as a cheap substitute to commercial adsorbent like activated carbons. The effects of pH, adsorbent dose, contact time, and initial dye and Cu(II) metal ion concentration on the adsorption efficiencies were investigated. Isotherm studies were conducted using Langmuir and Freundlich models, and thermodynamic studies were also performed. Adsorption of dyes was found to obey the Langmuir isotherm model and have endothermic process. The maximum adsorption capacities calculated from the Langmuir isotherm were found to be 88.18 and 2.9 mg/g for methyl orange dyes.