The creation of highly effective thermoelectric materials led up to an intensification of research activity in low-dimensional structures [1]. The paper presents an analysis of new approaches to improve the figure of merit ZT for nanostructures on the base of compounds IV-VI. The optimal thermoelectric characteristics of quantum dots, wires and wells superlattices are determined. Thickness dependences of kinetic parameters of quantum wells (QW) based on IV-VI compounds show non-monotonic oscillatory behavior that is associated with size quantization due to carrier movement restrictions in one direction . On the basis of theoretical model of rectangular quantum well with infinitely high barriers the dependences of thermoelectric parameters on nanostructures thickness of IV-VI compounds (PbTe, PbSe, PbS, SnTe) are investigated. Theoretically shown that in such structures it has place nonmonotonous, oscillation change of power factor S2σ with well width. It was determined the ddependence of Fermi energy and effective mass in the respective structures. It was identified and shown the determinative influence of geometric parameter on the band gap or overlap values of the quantum wire, quantum wells superlattice and the stack of quantum dots. Fig. 1 shows that the experimental dependence of the thermoelectric power factor on the thickness of nanostructures PbTe: Bi on glassceramics at the room temperature is characterized by a nonmonotonic behavior. Natural to assume that such behavior is due to quantization of energy carriers by restricting their movement in the potential well. The increasing of the well width on the value of half the Fermi wavelength leads to a new subband below the Fermi energy. When a new subband is filled, in the density of states there is a jump, which leads to oscillating behavior. Using the above theoretical model there were obtained the dependences of TE coefficients on the width of QW PbTe:Bi, which are characterized by nonmonotonic oscillating behavior (Fig. 2). This calculation of values are in rather good agreement with the corresponding experimental dependences (Fig. 1).figureFig.1. Experimental dependence of the thermoelectric power S2σ on the thickness of the nanostructures PbTe:Bi on glassceramics at T= 300K. Fig. 2. Theoretical dependence of TE power S2σ on the width of the QW PbTe: Bi in the model of infinitely deep potential well at T = 300 K.