The necessity to safeguard the environment has increased the potential of enzyme usage in textile processing to ensure eco-friendly production. Laccase enzyme formulation has been used in textile processing such as biobleaching, dyeing, rove scouring, finishing, neps removal, printing, wash-off treatment, dye synthesis and effluent treatment. However, a high cost associated with biocatalyst production is still a hindrance to their use. Pleurotus ostreatus is a white-rot fungus that produces a ligninolytic enzyme complex rich in several laccase iso-enzymes. The main objective of this study is optimize influence of pH and stability of divalent metal ion-immobilzed crude laccase enzyme towards decolourization of prototype textile dyes such as Reactive red 80 (Red F3B) and Reactive blue 21(T Blue G). Wheat bran is used as a lead candidature for production of lignolytic enzyme using Pleurotus osteratus by solid state fermentation. Two divalent metal ions such as Zn2 + and Ca2 + were selected to study the influence of metal ions towards the dye decolourization. Results revealed that Ca2 + ion was better compared to Zn2 + ion towards enzyme immobilization and its influence on dye decolourization in the optimal pH 5.5. Finally, interactions between laccase and dyes were studied exclusively using Insilco structure based molecular docking methods.