. Effects of three pre-emergent herbicides on five rice cultivars seedling emergence, were studied in Pelotas, at the Unidade de Execução de Pesquisa de Âmbito Estadual of the Empresa Brasileira de Pesquisa Agropecuária (UEPAE de Pelotas - EMBRAPA), in 1982. This experiment was carried out in greenhouse conditions, using a sandy soil with a wilting point of 5.8% and a field capacity of 15.5%. The herbicides Butachlor, Pendimethalin and Oxadiazon, respectively, were applied at the rates of 2.95, 1.50 and 1.00kg/ha; the cultivars used were Bluebelle, Brazos, EEA-406, BR-IRGA 409 and BR-IRGA 410. The effects were evaluated through the speed of emergence index, the initial stand and seedling dry weight at twenty-eight days after seeding. Results indicated that the herbicide Butachlor, was the most tolerated by all rice cultivars studied. Also, it was observed that the herbicide Oxadiazon reduced the initial stand of BR-IRGA 410 but did not influence the speed of emergence and the dry weight of individual seedling. The initial stand of Bluebelle, Brazos and EEA-406 cultivars was reduced by fitotoxicity caused by Pendimethalin, but speed of emergence and seedling dry weight of all cultivars studied were not affected by this herbicide.