Purpose: This study's objective was to assess the possible therapeutic and ameliorative effect of adipose derived mesenchymal stem cells (ADMSCs) on the overactive bladder (OAB) induced by bladder outlet obstruction (BOO) through the evaluation of some of oxidative stress, and anti-apoptotic markers in the bladder tissue, in addition to histopathological examinations. Methods: Regarding this investigation, Fifty female Sprague-Dawley mature rats with age (6 weeks) weighing 180 ± 20 gm. were divided into four groups at random as the following:  normal control group (n=10), OAB group (n=20) and OAB+ADMSCs group (n=20): After 4 weeks of BOO, 1x10⁶ of ADMSCs were once directly injected into the bladder's anterior wall's sub-mucosal layer .On the day 28 after the injection of ADMSCs, the scarifying of the animals were done and the bladder samples were collected from all rats groups. Catalase (CAT) activity and malondialdehyde (MDA) were measured in bladder tissue homogenates from all rats groups as oxidative stress markers. Also, gene expression of both apoptotic marker B-cell lymphoma 2 (Bcl-2) of bladder tissue of all rats groups was determined. Furthermore, histopathological changes in the bladder mucosa were detected in all different rats groups. Results: OAB+ADMSCs group showed statically significant higher expression (p<.001)  of antioxidant marker (catalase) when compared by OAB group and totally inversed with  the malondialdehyde that show statically significant lower expression (p<.001) when compared with OAB group. There was a significant increase (p<.001) in the anti-apoptotic markers B-cell lymphoma 2 (BCL2) in comparison to OAB group .The bladder's structure of overactive rats which treated with ADMSCs significantly improved. Conclusions: The results manifested the effective role of ADMSCs in enhancing the recovery of the bladder after the induction of OAB.