Background: Overactive bladder (OAB) syndrome, consisting of urgency, with or without urgency incontinence, often with frequency (voiding more than eight times in a 24- h period) and nocturia (need to wake up one or more times per night for urination), is a highly prevalent disorder with a significant impact on quality of life (QoL). Objective: To evaluate the safety and efficacy of mirabegron 50 mg in comparison to solifenacin 5 mg in the treatment of female patients suffering from overactive bladder symptoms. Patients and Methods: This prospective randomized study was conducted in Zagazig University Hospitals during the period From November 2018 to April 2019. Thirty consecutive female patients aged from 18 to 65 years old were included in this study. Results: Mirabegrone significantly was associated with hypertension only in one case, and Solifenacine significantly was associated with blurred vision, constipation and dry mouth. Comparison between mirabegron and solifenacin group according to day and night frequency, urge and urge incontinence pretreatment showed that there was no significant difference between both groups. Comparison between mirabegron and solifenacin groups according to day and night frequency, urge and urge incontinence after taking mirabegrone or solifenacin showed that mirabegron group was significantly lower as regards day and night frequency also in urgency and urgency incontinence post treatment. Conclusions: Solifenacin and mirabegron were effective in improving over active bladder symptoms. Mirabegron showed greater tolerability with fewer patients discontinuing therapy because of side effects. mirabegron can be considered as the drug with the better balance between efficacy and tolerability in the treatment of OAB.