As exosome therapy is a promising treatment in neurological disorders including epilepsy, the present study aimed to evaluate the effects of exosomes obtained from human adipose-derived stem cells (ADSCs) on pentylenetetrazol (PTZ) model of epilepsy in mice. Thirty adult mice were divided into PTZ, diazepam + PTZ, and exosome (5, 10, and 15 µg) + PTZ groups. The exosomes were administered intranasally 30 min before PTZ injection. The seizure latency, tonic-clonic onset, seizure duration, and mortality protection rate were monitored. Also, the level of hippocampal malondialdehyde (MDA), the oxidative stress marker, was evaluated. Exosomes in 5 and 15 µg concentration significantly increased seizure latency. Only 15 µg of exosomes induced a considerable delay in tonic-clonic onset. Seizure duration was significantly attenuated in the 5 µg exosome group. In addition, the 5-µg exosome indicated the highest mortality protection rate. Furthermore, the MDA level was significantly reduced in all animals treated by exosomes. Exosomes obtained from human ADSCs could alleviate epileptogenesis induced by PTZ maybe through reducing hippocampal oxidative stress.