The aim of this research is to determine the forage yield, quality and physiology of a Panicum spp. cv. Massai pasture in response to two grazing intensitiesand three irrigation depths. In Tocantins State, the difference between the average monthly minimum and maximum temperature reaches more than 16ºC, evenso, the lowest base temperature observed does not compromise the development of tropical forages. More than 93% of rainfall occurs between October andApril. This way, between May and September, there is a huge reduction of forage production due to water deficit. To achieve satisfactory economical results isdesirable to have a good distribution on forage production along the year. Assuming that there is enough light and temperature during all year, the onlyfundamental production factor not fully attended is the amount of water. Simulation studies have shown the great potential of the region for forage productionusing irrigation, specially during winter season. Understanding how is the response of irrigated pasture to Tocantins soil and climate conditions willcontribute to adjust the grazing management and increase the annual forage production, achieving higher yield in the whole system.