78 pediatric patients affected by acute otitis media were selected and randomized into two balanced groups of treatment: brodimoprim, at the dosage of 200 mg once-a-day on the first day and of 100 mg once-a-day on the following days, and cefaclor at a dosage of 40 mg/Kg/day in three doses. Brodimoprim resulted more efficacious in the reduction of symptoms, especially hypoacusis and tinnitus (p < 0.05 between treatments); tympanometry showed a higher number of normalizations in the brodimoprim group, without significant differences between treatments. Both drugs resulted active against most of isolated bacterial strains. Side effects were reported in 4 patients treated with brodimoprim and in 6 patients in the control group.