Dextranomer/hyaluronic acid copolymer (Zuidex(R)) is a new bulking agent. There is little data about the complications of using this substance as urethral bulking agent for the treatment of urinary stress incontinence. We are presenting a 59-year-old female patient who developed a suburethral mass and urinary retention after zuidex urethral injection. A stepwise approach for treatment was followed. Complete excision of the mass was the only curative procedure that succeeded.