In present work, the performance and effectiveness of flower-shaped Zinc oxide nanoparticles (ZON) synthesised by hydrothermal method was evaluated for the adsorption of Victoria Blue B (VB B) dye from aqueous solution. ZON were characterised by using XRD, FTIR, SEM, EDX and DLS. Batch mode adsorption experiments were carried out to optimise the process conditions viz., pH, adsorbent dose, dye concentration, temperature, etc. The adsorption of cationic dye onto ZON surface was illustrated by Langmuir and Temkin isotherm models. The mechanism of dye adsorption onto the nanoparticles was explained by pseudo-second order kinetic model (R-2 >= 0.997). The thermodynamic parameters including Gibb's free energy (Delta G(0)), enthalpy (Delta H-0), and entropy (Delta S-0) were studied at different temperatures (10-70 degrees C). The maximum adsorption capacity of VB B dye onto ZON was achieved up to 163 mg/g at pH 6.0 and temperature 27 +/- 1 degrees C. (C) 2016 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.