A dysregulation of the brain-bladder control network has been revealed by the functional brain imaging studies. However, the brain functional connectivity strength (FCS) of OAB still remains unclear. Our study investigated the changes of intrinsic whole brain functional connectivity pattern in OAB using FCS. Patients with OAB have impaired pattern of FCS, which shows abnormal short-range and long-range FCS in brain regions associated with brain-bladder network. Behavioural treatments of the OAB based on fMRI may provide new sight into clinical practice.