In this paper, the blend nanofiber (poly(vinyl alcohol) (PVA)/chitosan (CS)/diethylenetriamine (DETA)/ethylenediamine (EDA): PVA/CS/DETA/EDA) was prepared by electrospinning and cross‐linked by glutaraldehyde. The cross‐linked blend nanofiber by glutaraldehyde (CBNG) was characterized by FTIR and SEM. The homogenous surface diffusion model (HSDM) was used for expressing the dye adsorption on CBNG from colored wastewater. Experimental data were used to calculate the isotherm parameters as well as the kinetic parameters describing mass transfer resistances due to film diffusion (kf) and diffusion coefficient (Ds). The sum square error (SSE) values for the adsorption of Acid Red 18 (AR18), Direct Blue 78 (DB78), and Direct Red 23 (DR23) were 0.0221, 0.0632, and 0.0038, respectively. Thus, the experimental and theoretical data showed a good agreement. Dye removal by CBNG followed the Langmuir isotherm and pseudo‐second order kinetics models. Thermodynamic studies indicated dye adsorption onto the nanofiber was an endothermic, spontaneous, and physisorption process. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1634–1642, 2017