Abstract Purpose To evaluate safety and efficacy of topical cyclosporine with a cationic emulsion versus vehicle in vernal keratoconjunctivitis (VKC) in children. Methods Vernal keratoconjunctivitis of 118 children (range 4 yo to 21 yo) diagnosed with giant papillae were randomized in 3 groups. During one month the first group was treated topically QID with cyclosporine 0,05%, or cyclosporine 0,1%, or with vehicle. For the next two months the treatment was similar except for the third group randomized to cyclosporine 0,05% or cyclosporine 0,1%. Patient subjective improvement (5‐points ordinal scale) was the primary criterion. Resampling simulations have been carried out to generate success rate distributions. Objective evaluation was a secondary criterion with corneal fluorescein staining appreciation. Results The sex ratio of VKC was 1:4,4. Seasonal forms represented 23,7% of patients. The topical application of cyclosporine was rated comfortable by more than 76% of the patients at D28 and at 3 months. At D28, all groups showed subjective improvement; however when expressed in term of success/no success, subjective improvement was obtained for 89,8%, 84,6% and 70,0% of patients respectively with cyclosporine 0,05%, 0,1% and vehicle. Using resampling simulations, both success rates of 0.05% and 0.1% dosages were statistically significantly different (p<0.01) versus vehicle. Improvement (p<0.01) in overall rating of objective signs and corneal fluorescein staining was shown with cyclosporine 0,05%, 0,1% versus vehicle. Conclusion Treatment by cyclosporine with cationic emulsion formulation appears well tolerated and efficient in children with VKC. New larger studies are necessary to confirm these first results.