Treatment of positive margins after solid tumor resection remains a significant challenge for clinicians. Owing to unique structural features, electrospun nanofibrous mats are promised to be an implantable antitumor system through the delivery of active agents in a controlled manner. In this study, we utilized sequential electrospinning to fabricate a multilayer mat in which gemcitabine (GEM) and cisplatin (CDDP) were electrospun individually in distinct layers. By designing the structure, the multilayer mat could deliver antitumor agents sustainedly and prolong the release of GEM, which is loaded in the inner layer. In vitro assays show that the multilayer mats effectively inhibit bladder cancer (BC) cells and elevate apoptosis. In animal models of BC, the implantable drug-loaded fibrous mat can effectively treat positive margins and prevent local recurrence. Moreover, the local delivery of GEM and CDDP significantly lowers liver toxicity compared with systemic chemotherapy. In summary, a multilayer nanofibrous mat is developed for the localized and controlled delivery of GEM, dramatically improving the treatment of residual tumors and preventing BC recurrence. Impact statementThe designed multilayer nanofibrous mats can achieve two chemotherapeutic drugs (gemcitabine and cisplatin) co-loading and time-programmed sustained release, significantly improving our previous study. The antitumor effect of the drug-loaded mat in vivo and in vitro was sufficiently demonstrated. We expect to bring a new strategy of topical chemotherapy for treating positive surgical margins in bladder cancer.