The paper is dedicated to the problem of placing roots of interval system characteristic polynomial the coefficients of which are included in a parametric polytope, according to desired control quality. To provide applicable values of stability degree and oscillability degree, a pair of dominant poles is placed in desired areas of a complex plane. Other poles of the system, which are unrestricted poles, are placed in a desired allocation area, the border of which is defined to observe the poles dominance principle. In order to place poles according to desired control quality, a set of parametric polytope's vertices, which determine poles allocation, is found on the basis of angular properties of interval root locus. The parameters of a controller providing desired allocation of dominant and unrestricted poles are found with the help of D-partition basing on the previously obtained vertex polynomials.