Resumo. This study aimed to evaluate the fiber dimension of Dendrocalamus giganteus culms in 2-6 years old. Samples from basal portion of culms were macerated and sliced in sliding microtome for dimension fibers evaluation and histological cut production. Results showed that fibers increased in length with culms age, being the smallest and the biggest lengths 3266 and 3878.57 μm, observed in 3º and 6º years, respectively. The fibers showed smaller and bigger wall thickness in 6º and 2º years, with value of 7.11 and 10.46 μm, respectively. The anatomical tissue of culms varied from 12.8, 47.6 and 39.6 for vascular bundles, fibers and parenchyma, respectively.