Researching on Methyllen Blue dye treatment ability with Nano material (CoFe₂O₄ synthesized by co-precipitation method) combined with Biogum (extracted from Osaka Seeds (Cassia Fistula Linn). Research results show that with Biogum base material fully covered by magnetic nanoparticles of size 70 - 95 nm (SEM) and the presence of several specific functional groups for biogum and ferromagnetic oxide nano (FT-IR). When adding OH group to nano material, the adhestive ability to biogum and the size of the particle does not change. Results of comparative studies on the application of Nano-Biogum and Nano-OH-Biogum materials showed that when studying the dyeing color of Methylene blue, the treatment efficiency is from 62.43 to 78.72%, decreasing from 349.67 Pt-Co, 74.41 Pt-Co at pH 6 - 7 and dosage at 1.5 g/L. Based on the above results, Nano - Biogum is able to treat dyeing color better than Nano OH - Biogum. Therefore, Nano - Biogum can become suitable material for the application of color treatment in practice.