In the Dominican Republic, the area planted with coffee is 132,500 ha which produces an annual harvest of 36,636,364 kg through the efforts of more than 50,000 coffee farmers. Since 1997, the broca (Hypothenemus hampei) pest has infested the coffee fields in the country and has reduced crop yield and quality. The objectives of this study were to evaluate the influence of altitude and harvest period on the incidence of the broca incidence and on coffee bean grain quality. The experimental design was a completely randomized design with a factorial arrangement with 4 replicates. The twelve treatment combinations were formed from four altitudes (400-500, 600-700, 850-950 and 1000- 1100 meters) and three harvest periods (November, December and January). The variables were crop management, percentage of infected grains, and commercial quality of the beans. The results showed that from 78.4% to 100% of the farmers controlled the shade at 850-950 meters of altitude while 74.75% did so at 400-500 meters of altitude. The higher incidences (22.33 % and 20.00 %) of infected beans were at 400-500 and 600- 700 meters of altitude, respectively. The lineal regression analysis showed an inverse relationship between altitude and percentage of infected grains. Moreover, this analysis showed a direct relationship between altitude and bean quality AAA, but an inverse relationship with quality AA and A. The highest percentage of beans with quality AAA (69.44 %) and AA (52.61 %) were at 1000 -1100, and 400-500 meters of altitude, respectively. The data suggest that altitude affects the yield and quality of coffee beans.