Bacillus Calmette-Guerin (BCG) is a vaccine derived from attenuated strains of Mycobacterium bovis. Mycobacterium bovis BCG-based therapy is considered an effective alternative for bladder carcinoma in situ when exclusive transurethral resection is inadequate. Among the complications associated with therapy, there are few reports in the literature on reactive arthritis. We report the case of a 56-year-old woman who develops predominantly peripheral spondyloarthritis, following instillation of BCG, as preventive treatment of relapse onset high-grade urothelial carcinoma after surgical resection.