Earlier the quasi-isothermal model of distribution of mass was constructing. Suppose, that the third quadratic in the velocity integral of motion exists. Hence, the potential of this model is of Stäckel’s type. The theory of constructing such models was developed by G.G. Kuzmin. Some results for the quasi-isothermal model is presented in this work. An application of this model to our Galaxy was studied. Comparing the model curve of circular speed with observational data, which were obtained from observations of neutral hydrogen, estimations of structural and scale parameters of this model are found. Equidensities were drawed. Also a two-component model, where second component is described by the generalizedisochrone potential, is constructed. For this model the expression for spatial density was obtained. Estimations of structural and scale parameters for our Galaxy were found. Equidensities are presented.