Neurogenesis in the adult brain comprises the entire set of events of neuronal development. It begins with the division of precursor cells to form a mature, integrated, and functioning neuronal network. Adult neurogenesis is believed to play an important role in animals’ cognitive abilities, including learning and memory. In the present study, significant neuronal differentiation-promoting activity of 80% (v/v) ethanol extract of P. cocos (EEPC) was found in Neuro-2a cells and mouse cortical neural stem/progenitor cells (NSPCs). Subsequently, a total of 97 compounds in EEPC were identified by UHPLC-Q-Exactive-MS/MS. Among them, four major compounds—Adenosine; Choline; Ethyl palmitoleate; and L-(-)-arabinitol—were further studied for their neuronal differentiation-promoting activity. Of which, choline has the most significant neuronal differentiation-promoting activity, indicating that choline, as the main bioactive compound in P. cocos, may have a positive effect on learning and memory functions. Compared with similar research literature, this is the first time that the neuronal differentiation-promoting effects of P. cocos extract have been studied.