ABSTRACT The objective of this study was to determine the optimal dietary concentration of zinc and manganese on the performance characteristic and the requirement of these trace minerals derived from organic sources for broilers from 1 to 42 days of age. In experiment 1, zinc was evaluated, whereas manganese was evaluated in experiment 2. In each experiment, 320 males chicks were distributed in iron mesh metabolic cages (0.9m x 0.7m x 0.5m), according to a completely randomized experimental design in eight treatments with five replicates of eight birds each. In experiment 1, zinc sulfate was included at 0,60 and 100mg/kg and zinc methionine at 20, 40, 60, 80 and 100mg/kg. In experiment 2, manganese sulfate was added at 0, 65 and 105mg/kg and manganese methionine at 25, 45, 65, 85 and 105 mg/kg. Trace mineral requirements were determined comparing only organic trace mineral levels. The evaluated trace minerals (zinc and manganese) did not influence broiler performance, independently of source or level. It was concluded that the requirements of broilers from 1 to 42 days of age were supplied with no addition of zinc or manganese, under the conditions of the present experiments. However, under commercial rearing conditions, which are more challenging, the use of levels higher than 33.00 mg/kg and37.80 mg/kg of zinc and manganese, respectively, may be justified.