Abstract: Objective To investigate the effect and mechanism of terazosin hydrochloride combined Mecobalamin on diabetic neurogenic bladder. Methods Ninety cases of diabetic neurogenic bladder in our hospital from March, 2015 to June, 2016 were randomly divided into 2 groups, with 45 cases in each group. The patients in the control group received alpha lipoic acid, while the patients in the treatment group received terazosin hydrochloride combined with Mecobalamin based on alpha lipoic acid. Before and after the intervention, serum oxidative stress indices, neural activity index, early renal injury index were tested. Urodynamic were analyzed, and the clinical efficacy and adverse reactions were compared. Results The effective rate of the treatment group was 88. 89%, which was higher than that (71. 11%) of control group (P < 0. 05). After the intervention, maximum urinary flow rate, detrusor pressure at maximum urinary flow rate, glutathione (GSH), superoxide dismutase (SOD), brain derived neurotrophic factor (BDNF) of the treatment group were significantly increased, and significantly higher than those of the control group (P < 0. 05). After the intervention, bladder residual urine volume, bladder maximum pressure capacity, oxygen activity (ROS), malondialdehyde (MDA), substance P (SP), neuropeptide Y (NPY), cystatin C (CysC), gamma glutamyl-transferase (γ-GT) of the treatment group were significantly reduced, and significantly lower than those of the control group (P < 0. 05). There was no significant difference on the incidence of adverse reaction between the two group (P > 0. 05). Conclusion Terazosin hydrochloride combined Mecobalamin have exact efficacy on patients with diabetic neurogenic bladder, it can reduce the CysC andγ-GT level, improve the oxidative stress and neural activity, with high safety.