© 2016 Elsevier B.V. All rights reserved. 0-3 mol% Gd-doped MoO 3 nanobelts were synthesized by hydrothermal method for using as visible-light-driven photocatalysts. The effect of Gd dopant on phase, morphologies and photocatalytic activities of MoO 3 nanobelts was investigated. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that pure and Gd-doped products are orthorhombic MoO 3 and Gd-doped MoO 3 nanobelts with their growth along the [001] direction. Photocatalysis of 0-3 mol% Gd-doped MoO 3 nanobelts were monitored through degradation of methylene blue (MB) solutions under visible radiation. The Gd-doped MoO 3 nanobelts show better photocatalytic performance than pure MoO 3 nanobelts. The 3 mol% Gd-doped MoO 3 photocatalyst exhibits the highest visible-light-driven activity for photodegradation of MB solution of 99% within 60 min.