This experiment was carried out at the Alfredo Volio Mata Dairy Cattle Experimental Station in Costa Rica, at an altitude of 1542 masl, where there is an average annual rainfall of 2050 mm, temperature of 19.5 C and relative humidity of 84%. A mulberry bush plantation was divided into three plots: with a distance of 60, 90 and 120 cm between rows and plants. Each plot was uniformly pruned at two heights: 30 and 60 cm from the ground. During a 336-day period, these subplots were pruned consecutively every 56th, 84th and 112th day. The planting distance and the pruning height produced small variations in the chemical composition of the mulberry leaves and stems. The cutting frequency produced changes in the composition of the leaves and stems. Nevertheless, the differences in dry matter, crude protein, structural carbohydrates and total ashes in the leaves were not higher then 3% in experimental frequencies. In the stems the greatest changes were 9% and they were produced in the content of the dry matter, cellular wall and in some of the structural chemical components, such as cellulose. The cutting number within each frequency significantly influenced the chemical composition of the  leaves and the stems.