The effect of different components on the structure of ultrabasic calcium sulfonate during formation of a complex system was investigated by potentiometric titration and IR spectroscopy. Colloidal calcium carbonate has a calcite structure in the initial simple ultrabasic calcium sulfonate, in the intermediate model systems containing calcium tetraborate or 12-hydroxystearate, and in the final ultrabasic calcium sulfonate, and this structure does not change on conversion of the simple sulfonate grease into a complex grease. Micelles of the complex ultrabasic sulfonate grease consist of nuclei containing colloidal calcium carbonate and tetraborate coated with a calcium sulfonate and 12-hydroxystearate adsorption shell.