Gender differences in prevalence, tumor invasiveness, response to treatment, and clinical outcomes exist in different types of cancer. The aim of this article is to summarize the sex disparities in bladder cancer diagnosis and treatment and try to suggest areas for improvement. Although men are at a higher risk of developing bladder tumors, women tend to be diagnosed with more advanced stages at diagnosis and are more likely to present with upfront muscle-invasive disease. Non-urothelial histological subtypes are more frequently reported in women. Regarding non-muscle-invasive bladder cancer (NMIBC), several studies have shown that women have a higher risk of disease recurrence after treatment with Bacillus Calmette–Guerin, due to different immunogenicities. In localized muscle-invasive bladder cancer (MIBC), neoadjuvant chemotherapy and cystectomy are less likely to be performed on women and sexual-sparing procedures with neobladder diversion are rarely offered. Finally, women appear to have a poorer prognosis than men, potentially due to the sex-associated intrinsic features of hosts and tumors that may drive differential therapeutic responses, particularly to immune-based therapies. Women are also more likely to develop severe adverse events related to systemic therapies and are underrepresented in randomized studies, leading to a gap between the real world and trials. In conclusion, studies investigating the role of sex and gender are urgently needed to improve the management of urothelial carcinoma.