Post-traumatic stress disorder (PTSD) is a debilitating psychological condition characterized by intrusion, avoidance, negative cognitive patterns, and increased arousal after exposure to life-threatening stressors and trauma. The major pharmacologic approach for treating PTSD is using selective serotonin reuptake inhibitors, but they do not fully take care of all aspects of this complex disorder; therefore, new PTSD treatments are urgently needed. In a pilot study, we explored the potential of Ziziphus jujuba var. spinosa, traditionally used to treat insomnia and nervous, for PTSD. Thereafter, we aimed to investigate if spinosin, the main component of Ziziphus jujuba var. spinosa, could effectively alleviate key symptoms of PTSD in the single prolonged stress (SPS) mouse model, a well-known animal model for simulating PTSD. Spinosin (3 mg/kg, p.o.) mitigated anxiety-like behavior by elevated plus-maze test and marble burying test, and alleviated depressive-like behavior by splash test and tail suspension test, and improved cognitive dysfunction measured by Y-maze test and novel object recognition test. Further, spinosin reduced increased fear memory examined by fear extinction test. Finally, in the amygdala, spinosin normalized the levels of the stress response regulators including glucocorticoid receptor, NF-κB, NOS, and Nrf2 via 5-HT_1A receptor. These findings suggest that spinosin may be a potential therapeutic candidate for alleviating the multifaceted symptoms of PTSD.