Ceria nanoparticles are one of the most vital nanomaterials for a varied range of applications in catalysts, fuel cell, chemical-mechanical polishing for microelectronics, phosphor/ luminescence, and metallurgical and glass/ceramic applications. These applications are mainly based on cerium’s high thermodynamic affinity for oxygen and sulphur, its potential redox chemistry involving Ce(III)/Ce(IV), and absorption/excitation energy bands related to its electronic structure [1]. Newly, much attention has been paid to the CL of nanomaterial systems, to improve the sensitivity and the stability. Semiconducting and metallic NPs used as catalysts in CL reactions have provided new methods to improve the sensitivity and extended new applications of this mode of detection [2]. It is perhaps interesting to mention that topiramate (C12H21NO8S) is an anticonvulsant (antiepilepsy) drug. This medication is prescribed for treatment of diseases such as epilepsy, bipolar disorder, alcholism, bulimia nervosa, obesity, migraine, post-tranmatic stress disorder and mood instability disorder [3]. Fig. 1. SEM image of CeO2 NPs In this work, CeO2 nanoparticles (NPs) were prepared by using quick precipitation method and, then, were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) (Fig. 1). It was found that CeO2 NPs present oxidase-like activity and increase the intensity of the luminol-O2 CL reaction. Moreover, it was found that topiramate could enhance the intensity of CeO2 NPs-luminol-O2 CL reaction. Based on these findings, a simple and sensitive CL method for the determination of topiramate was proposed. The linear dynamic range of the CL method for determination of topiramate was 4.0 ×10-6 – 1.0 ×10-5 mol L-1, with a limit of detection (LOD) = 3.9 ×10-6 mol L-1. The relative standard deviation (RSD%) of the CL method was 1.37% (n = 9). The CL method was used for the measurement of concentration of topiramate in pharmaceutical preparations.