Porous alumina with interconnected structure is synthesized by a simple approach assisted by a polycondensation of resorcinol–formaldehyde (RF) mixture. The results show significant increase in surface area because of the porous network of the RF gel and the effectiveness of the RF gel in retarding growth of alumina grains during calcination. The product obtained has the surface area of 68 m2/g even after the calcination at 1200°C to convert it to α-alumina, whereas the surface area of the product prepared without the RF gel is only 10 m2/g. Nevertheless, the process is not direct templating technique since the interaction between the precursor of alumina, i.e., aluminum acetylacetonate (Al(acac)3), and the RF mixture occurs and alters the gel structure. The formation of alumina clusters via the sol-gel process takes place as the network of RF gel is progressively formed.