The color pollution is typical in the textile wastewater and requires a lot of costs for treatment. This study aim to investigate the ability to degrade Congo Red dye in the group of popular diazo dyes by selected strains which were isolated from typical textile dyes in Vietnam. Some influence factors such as shaking conditions, adding sugar sources, changing culture media and combination of single strains to decolorization performance were also assessed using the Congo Red calibration through UV-Vis spectrometers. The results show that the isolation obtained in textile dyes wastewater 8 strains capable of Congo Red decolorization, the best strain was Aspergilus Niger which degraded nearly 90% of Congo Red 200mg/L after 14 days. The influence of shaking conditions of 180 rpm will better 15% decolor performance than static conditions and the addition of glucose also increases treatment time efficiency. The changing medium of PDA and mineral medium Czapez will have certain effects on the effectiveness of the treatment process. Expecially, the combination of strains of Aspergillus Niger and Streptomyces Thermodiastaticus illustrated that the Congo Red degradation performance increased by nearly 10% and the contact time was reduced to 50%. Overall, some selected strains showed good decolorization ability after 14 days, which compares to the control sample.