The nano-morphologies of anodic porous alumina formed via anodizing in a new electrolyte, acetylenedicarboxylic acid (ADCA), are described. Anodic oxides grew uniformly on the aluminum at voltage of 87.5-95.0 V, but a burned black oxide film was formed at higher voltage. The burning voltage and the current density under steady-state oxide growth decreased with solution temperature. An anodic porous alumina film with a cell size of 250 nm and nanopores measuring 100 nm could be successfully obtained by ADCA anodizing. The anodic porous alumina possessed numerous non-straight nanopores due to the branching and extinction of the nanopores during anodizing.