Background: Sleep deprivation (SD) is a common condition affecting many people in modern life. Edaravone (Eda) is a neuroprotective drug, but whether it can improve cognitive impairment caused by SD remains unclear. Methods: Animals received oral gavage doses of Eda (10, 20, and 40 mg/kg) for 8 and 5 days before and during SD. Starting from the 6th day, a modified multiple platform model was used to produce SD in mice for 72 h. The Lashley III maze was used for evaluating spatial learning and memory. Malondialdehyde (MDA) in the hippocampus and serum corticosterone were assessed. Total antioxidant capacity (TAC) and the activity of the enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD) were measured. Growth-associated protein 43 (GAP-43), synapsin 1 (SYN-1), post-synaptic density-95 (PSD-95), synaptophysin (SYP), and signs of inflammation were detected using Western blotting. Results: SD caused cognitive impairment, whereas Eda pretreatment warded off such an effect. While serum corticosterone levels rose with SD as well, they decreased in SD mice that received Eda (p < 0.05). Moreover, Eda normalized the SD-induced decline in hippocampal activity of SOD and GPx, lowered MDA levels, and elevated TAC (p < 0.01). Additionally, the hippocampal levels of GAP-34, SYP, SYN-I, and PSD-95 were elevated, while IL-1β and tumor necrosis factor α (TNF-α) were lowered following Eda pretreatment (p < 0.05). Conclusions: SD caused memory impairment; however, pretreatment with Eda improved memory by upregulating synaptic proteins in the hippocampus and having anti-inflammatory and antioxidant effects.