Overactive bladder (OAB) is a symptom syndrome characterized by urgency frequency with or without urgency incontinence, usually no metabolic or anatomical disorders can be found and it may have great impact on quality of life. OAB symptoms were found to have a significant effect on the emotional well-being and productivity of those affected. Although there are several new therapeutic options with promising treatment outcome, antimuscarinic drugs remain the first line treatment and clinical effects with good tolerability have been confirmed. However, not all OAB patients can benefit from antimuscarinic agent, and this treatment has some adverse effects such as dizziness, dry mouth, blurred vision, and constipation, which are intolerable for some patients. Of these patients intravesical botulinum toxin (BoNT) injections provide an alternative treatment with a favorable efficacy.