Nano-rods and tremelliform Gd2O2S:Pr powders were prepared via a urea precipitation method using SO2 and SO42- as sulfuration agent, respectively. Gd2O2S:Pr nano-rods with diameter of about 200 nm were obtained while the scale of tremelliform Gd2O2S:Pr reaches tens of microns. Gd2O2S:Pr nano-rods exhibits better crystallinity and stronger luminescence intensity compared to that of tremelliform Gd2O2S:Pr. Intensive study on their formation process and mechanism is presented in this work. It is proposed that Gd2O2S:Pr nano-rods were obtained from Gd-2(SO3)(3).3H(2)O nano-rods synthesized via a dissolution-deposition process while tremelliform Gd2O2S:Pr is prepared via an oriented growth process using SO4 as sulfuration and regulation agent. As prepared Gd2O2S:Pr powders show strong green emission light at 512 nm under excitation of 318 nm ultraviolet light. Optimal concentration of Pr3+ is around 1 mol% since it exhibits the highest luminescence intensity at that concentration. This study is extremely prospective for the preparation and morphology control of sulphide luminescent materials. (C) 2016 Elsevier B.V. All rights reserved.