Assemblies of metal complexes have been shown to have a variety of catalytic functions in biological and industrial systems. Although many studies have been reported for the behavior of metal ions in organized solutions, a limited number of metal complex surfactants are isolated and well characterized for their structures, and thus their physical properties in solutions have not been extensively studied. Some of their characteristic features are unobtainable with conventional surfactants having no metal-complex moiety. In this review, we focus on the physical properties of metal complex surfactants with alkyl chained ligands in solutions. Metal complex surfactants having double chain N-alkylethylnediamine ligands provide various kinds of aggregates depending on solvents because of their moderate hydrophile-lypophile balance. Studies on other novel type aggregates composed of amphiphilic transition-metal complexes are also reviewed.