Five wheat cultivars were studied to manganese toxcity using four different levels of this element (0.11, 300, 600 and 1,200mg/l) in nutrient solution under constant temperature (25 ± 1°C) and pH 4.8. The tolerance of the plant was measured taking into account the central primary root length and the leaf and root total dry weight. The presence of high levels of manganese (300, 600 and 1,200mg/l) into the solution produced harmful effects in all wheat cultivars under study. The wheat cultivar BH-1146 was very sensitive to 300mg/l of Mn2+ and the cultivars IAC-5, IAC-17, Alondra-S-46 and Siete Cerros were tolerant to these amounts of manganese. Siete Cerros was the most tolerant to 600mg/l of Mn2+; IAC-5, Alondra-S-46 and IAC-17 were moderately tolerant and BH-1146 was very sensitive. At 1,200mg/l Siete Cerros and Alondra-S-46 showed the best tolerances. The manganese concentration in the leaves of all wheat cultivars increased when the levels of manganese increased into the nutrient solution. The iron concentrations in the leaves were not dependent of the different levels of Mn2+ into the nutrient solution so there were no iron deficiencies in the wheat plants under study. Greater tolerance to Mn2+ in Siete Cerros and Alondra-S-46 in relation to BH-1146, IAC-5 and IAC-17 appears to be due to a higher internal tolerance to high Mn2+ levels within its leaves and not to decreased Mn2+ uptake.