Li-stabilized K-beta/beta"-aluminas in the ternary system K2O-Li2O-Al2O3 were prepared via the sol-gel process and solid state reaction, respectively. Based on these different methods, a careful comparison of the phase transformation and crystalline shape and growth was made with respect to the calcination temperature. In the employed sol-gel process, stable sols of hydrated alumina Al2O3 (.) yH(2)O (190 < y < 210) were reacted with methanolic KOH and Li2CO3 dissolved in water, forming crystalline K/Li-inserted boehmite. Through thermal decomposition at about 430degreesC, this precursor was converted to a modified K/Li-gamma -alumina intermediate, which yielded the phase pure K+-beta"-alumina by calcinations at relatively low temperatures between 1100-1200degreesC. On the other hand, both beta/beta"-alumina phases with a maximum beta"-alumina phase fraction of about 50% appeared at 1300degreesC through the solid state reaction using fine a -alumina powder as a starting material. Non-calcined dried powder precursor after sol-gel treatment was uniform and fine and its mean particle size about 2 similar to 3 mum within narrow distribution range. According to the morphology analysis after sintering at 1600degreesC, the crystalline growth of the beta/beta"-aluminas prepared by sol-gel process has been rapidly achieved in contrast to the solid state reaction.