in this work was utilized the polymeric precursor method to synthesis ceramic powders of na+-b-alúmina. we were interested in determinate the initial quantity from sodium precursor and its effect on crystalline phase obtained. powders obtained were characterized using infrared spectroscopy (ftir), x-ray diffraction (xrd) and scanning electron microscopy (sem). the effect of the initial quantity of sodium in the sample was very important in the nature of the final product. if we used one stoichiometric quantity of naoh, to obtain naal11o17 compound, we obtained a-alúmina as finish product (1450oc). on the other hand, b-alúmina and/or na2al2xo3x-1 were obtained in samples treated thermicalment from 1000oc to 1350oc. when we used a higher quantity of naoh, sample non-stoichiometric, a solid with naal11o17 as majority phase was obtained.