the objective was to evaluate the effects of vitrification of immature bovine oocytes after in vitro culture, by the use of cryoprotectors ethylene glycol. oocytes from cows ovaries from slaughters houses were randomly alocated into three treatments. treatment 0 (control): frozen-thawed undesnude oocytes; treatment 1, immature vitrificated undesnude oocytes dehydrated for 5 minutes in each of the following solutions of 20, 20 and 40% of ethylene glycol, respectively, associated to 0.3 mol l-1 of trehalose and 20% of pvp, in media talp hepes, and, treatment 2, the same as treatment 1, but desnudes oocytes. after frozen-thawed of the oocytes (imersion in water bath at 30oc for 20 seconds), the oocytes were gradually rehydrated, in the following sequence of solutions: media talp hepes with 20% of ethylene glycol + 0.3 mol l-1 of trehalose + 10% of pvp and media talp hepes without ethylene glycol, trehalose and pvp, were washed three times. ultimately, the oocytes were cultured at 38.5oc, with 95% umidity and atmosphere of 5% of co2 for 24 hours. after culture, the oocytes were fertilized and the embryos cultured in vitro for seven days. the nuclear maturation were 81 (68/84), 19 (7/36) and 0% (0/31), for treatments 0, 1 and 2, respectively. the cleavage and development rates were: 56.4(102/181) and 54,9% (56/102), 1,7. (1/60) and 0,0% (1/60), 0,0 (0/71) and 0,0% (0/71), for the treatments 1, 2 e 3, respectively. these results show that the vitrification procedures, by the used protocols, are not indicated for bovine oocytes cryopreservation.