Herein, we report a facile one-pot solvothermal method to prepare unique oleic acid (OA) modified monodispersed mesoporous TiO2 nanospheres with carboxylate ligands from the oleic acid in the bidentate chelating linkage mode. The mesoporous OA-TiO2 nanospheres have a very large specific surface of nearly 510 m(2)/g. The oleic acid cannot only act as a binding ligand to control the shape of mesoporous TiO2 nanospheres, but also be benefit to enhance the visible-light absorption. The mesoporous OA-TiO2 nanospheres exhibit an excellent photocatalytic performance in the degradation of Rhodamine B and phenol under the visible light irradiation and show almost no attenuation after four cycles. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.