Standard teaching dictates that systemic therapy is required for treatment of onychomycosis. It is unknown whether topical antifungal therapy is effective for pediatric nail infections. This prospective, randomized, double-blind, vehicle-controlled study was conducted in the Pediatric Dermatology Research Unit at Rady Children's Hospital to determine whether topical antifungal therapy is efficacious for pediatric onychomycosis. Forty patients ages 2 to 16 years with nonmatrix onychomycosis were randomized 1:3 to ciclopirox lacquer or vehicle lacquer. Ciclopirox lacquer or vehicle was applied daily for 32 weeks, with weekly removal of the lacquer and mechanical trimming. Those with poor response were crossed over to active drug at week 12. Thirty-seven patients completed the 32-week study, and follow-up data were collected 1 year after completion of the study from 24 patients. Mycologic cure, effective treatment, and complete cure were assessed, as well as adverse events and effect on quality of life. Mycologic cure was 70% in the treated group and 20% in the vehicle arm (p = 0.03) at week 12. At end of the study (week 32), 77% of treated patients achieved mycologic cure and 71% effective treatment, compared with 22% of the control group. Ninety-two percent of those who were cured and followed for 1 year remained clear. Topical antifungal lacquer (ciclopirox) can be an effective option for children with nonmatrix onychomycosis. Pediatric onychomycosis does not always require systemic therapy and responds better to topical therapy than does adult disease.