The occurrence of circadian rhythm disorder in patients with Alzheimer's disease (AD) is closely related to the abnormal deposition of amyloid-β (Aβ), and d-Ser2-oxyntomodulin (Oxy) is a protease-resistant oxyntomodulin analogue that has been shown to exert neuroprotective effects. This study aimed to explore whether Oxy, a new GLP-1R/GCGR dual receptor agonist, can improve the Aβ-induced disrupted circadian rhythm and the role of GLP-1R. A mouse wheel-running experiment was performed to explore the circadian rhythm, and western blotting and real-time PCR were performed to assess the expression of the circadian clock genes Bmal1 and Per2. Furthermore, a lentivirus encoding an shGLP-1R-GFP-PURO was used to interfere with GLP-1R gene expression and so explore the role of GLP-1R. The present study has confirmed that Oxy could restore Aβ31-35-induced circadian rhythm disorders and improve the abnormal expression of Bmal1 and Per2. After interfering the GLP-1R gene, we found that Oxy could not improve the Aβ31-35-induced circadian rhythm disorder and abnormal expression of clock genes. This study demonstrated that Oxy could improve Aβ31-35-induced circadian rhythm disorders, and GLP-1R plays a critical role. This study thus describes a novel target that may be potentially used in the treatment of AD. © 2019 The Authors. CNS Neuroscience & Therapeutics Published by John Wiley & Sons Ltd.