A multi-anion dye (e.g. direct blending scarlet D-GLN) can intercalate into Mg–Al-layered double hydroxides (LDHs) which is confirmed from XRD, SEM, FTIR, DTG and ζ-potential analyses. The DGLN–LDHs hybrid with the hybridization amount 524mg/g DGLN exhibits a high adsorption capacity to cationic dyes, e.g. 1064mg/g for victorial blue B. The hybrid was used as a sorbent to treat cationic dye wastewater and the decoloration rate over 80% by adding only 5g/dm 3 . In addition, the resulting sludge was reutilized as a colorant filled in polymer materials and it exhibited the resistance to bleeding and fire. This work provides a new approach for the treatment of dye wastewater and reutilization of dye sludge.