Purpose: Erectile dysfunction (ED) is a common postoperative complication of pelvic surgery for which there is currently no effective treatment. This study investigated the therapeutic effects and potential mechanisms of adipose derived mesenchymal stem cells-derived mitochondria (ADSCs-mito) transplantation in a rat model of bilateral cavernous nerve injury (CNI) ED. Materials and Methods: We isolated mitochondria from ADSCs and tested their quality. In vivo, twenty male Sprague Dawley rats were randomly divided into four groups: sham operation group and CNI groups that received intracavernous injection of either phosphate buffer solution, ADSCs-mito or ADSCs. Two weeks after therapy, the erectile function of the rats was evaluated and the penile tissues were harvested for histologic analysis and western blotting. In vitro, the apoptosis rate, reactive oxygen species (ROS), mitochondria derived active oxygen (mtROS) and adenosine triphosphate (ATP) levels were detected in corpus cavernosum smooth muscle cells (CCSMCs) after the incubation with ADSCs-mito. In addition, intercellular mitochondrial transfer was visualized by co-culture of ADSCs and CCSMCs. Results: The ADSCs, ADSCs-mito and CCSMCs were isolated and identified successfully. ADSCs-mito transplantation notably restored the erectile function and smooth muscle content of CNI ED rats. Moreover, the levels of ROS, mtROS and cleaved-caspase 3 were reduced and the levels of superoxide dismutase and ATP were increased after ADSCs-mito transplantation. In CNI ED rats, the mitochondrial structure of cells in penile tissues was destroyed. ADSCs could transfer its own mitochondria to CCSMCs. Pre-treatment with ADSCs-mito could significantly decrease apoptosis rate, ROS levels and mtROS levels as well as restore the ATP level in CCSMCs. Conclusions ADSCs-mito transplantation significantly ameliorated ED induced by CNI, with similar potency to ADSCs treatment. The ADSCs-mito might exert their effects via anti-oxidative stress, anti-apoptosis and modulating energy metabolism of CCSMCs. Mitochondrial transplantation should be a promising therapeutic method for treating CNI ED in the future.