Background: Overactive bladder (OAB) is common in patients with multiple sclerosis (MS) with a limited number of treatment options. Objective: To investigate the effect of transcutaneous tibial nerve stimulation (TTNS) and pelvic floor muscle training (PFMT) with biofeedback on OAB symptoms in female MS patients. Methods: This study was conducted at the outpatient MS clinic in Istanbul. At baseline bladder diary, post-voiding residue (PVR), OAB, and Qualiveen Scales (QoL: Quality of Life; Siup: Specific Impact of Urinary Problems on QoL) were assessed. Patients were allocated to receive TTNS or PFMT daily for 6 weeks and reevaluated using the same tests. Results: Fifty-five patients (TTNS = 28, PFMT = 27) were included. Compared with baseline, both TTNS and PFMT groups improved in terms of OAB (p = 0.0001,p = 0.0001), Qualiveen-siup (p = 0.0001,p = 0.0001), Qualiveen-QoL (p = 0.002,p = 0.006), PVR (p = 0.0001,p = 0.21), frequency (p = 0.0001,p = 0.69), nocturia (p = 0.0001,p = 0.19), urgency (p = 0.0001,p = 0.0001), and urge incontinence (p = 0.0001,p = 0.0001). Between-group comparisons showed significant differences in 24-hour frequency (p = 0.002) in favor of TTNS. Conclusion: Our study demonstrates the efficacy of both TTNS and PFMT for managing OAB symptoms in MS, associated with a significant impact on QoL, but did not show superiority of the methods. Further studies are needed to explore differences between these two non-invasive treatments.