Eleven rice cultivars were studied in relation to aluminum toxicity using six different levels of this element (0, 10, 20, 30, 40 and 50mg/l) in nutrient solution under constant temperature (30±1°C) and pH = 4.0. Plant tolerance was measured taking into account the central primary root length and the total leaf and root dry weight. The presence of aluminum in the solution produced harmfull effects on all rice cultivars studied. The rice cultivars IR-8, IR-841 and IAC-899 were sensitive when it was added 10mg/l of Al3+ into the solution and the cultivars IAC-435, IAC-120, Pérola, Blue Bonnet, IAC-164, IAC-25, IAC-165 and IAC-47 showed tolerance to this Al concentration. The last cultivars presented tolerance even with 20mg/l of Al3+ in the solution. All cultivars were sensitive with 50mg/l of Al in the solution. The aluminum concentration increased and the Ca, Mg and K concentrations decreased in the leaf dry matter, for all cultivars under study, as aluminum concentration in nutrient solutions increased from 0 to 50mg/l.