Nutritional content and forage yield of Pennisetum purpureum varieties in Costa Rican Central Plateau. The experiment was conducted at the Alfredo Volio Mata Experimental Station belongs to the University of Costa Rica, located at an altitude of 1542 m, with annual rainfall of 2,050 mm. Biomass production was compared among Taiwan Grass, King Grass, Elephant, Dwarf Elephant and Cameroon at two different cut ages. It was determined that King Grass and Taiwan produced the largest amounts of green and dry matter (15.3 and 13.9 t/ha, respectively) followed by Elephant, Cameroon and Dwarf Elephant (12.2, 6.9 and 4.7 t/ha, respectively). It was determined that the greatest production was obtained at 70 days of age due to production and physiological state of the plants. For Dwarf Elephant the optimal age was 98 to 112 days. The shaft:leaf relationship of the evaluated forages were always smaller than one, been the exception the Dwarf Elephant (1.73). Dry matter content increased with age, and the higher content was found in the leaves. Protein levels diminished with cutting age and showed higher levels in leaves than in shafts. Protein content of the Dwarf Elephant was 16.51% in the whole plant due to the greater production of leaves.