Bamboo is a natural resource, typical of tropical and subtropical regions, whose fibers are attracting interest to reinforce composite materials, due to its excellent mechanical properties. However, like all plant fibers, bamboo fibers present a high degree of hygroscopicity, swelling when water is present, limiting its use due to loss of durability. Thus, this work aims to study improvements in the flexural properties of bamboo through the process of hornification by wetting and drying cycles, a treatment that is widely used in pulps of wood or paper, leading to reductions in the water absorption and retention capacity of the fibers, reducing its pores and making its structure stiffer. The effects of 3, 5 and 10 wetting and drying cycles on the physical properties and mechanical behavior (flexure and modulus of elasticity) of the Moso bamboo species (Phyllostachys pubescens) were investigated. Regarding the physical properties, the variations in the bamboo water absorption and retention capacity were evaluated along the cycles, including evaluation of the dimensional variations of the vascular bundles at the end of the cycles, performed by means of analysis and processing of images obtained by a stereoscopic microscope. In addition, the flexural behavior was studied by means of four-point flexural tests, evaluating possible improvements in flexural strength, deflection and modulus of elasticity of the bamboo after the wetting and drying cycles, including analysis of the influence of shear on flexion. The physical analyzes showed that with the cycles there was a reduction in the water retention capacity of bamboo, as well as reductions in the surface area of its fiber bundles. In flexion, there was a gain of stiffness after the cycles, increasing the modulus of elasticity by 70 per cent.