The new zinc(II) complexes of general formula Zn(CH3CH2CH2COO)(2) . nL (where L = thiourea, urea; n = 1 or 2) were prepared and identified. The thermal properties of this compounds were investigated by thermal analysis (TG, DTG, DTA, DSC, DDSC). The gaseous products of thermal decomposition were detected by IR spectroscopy and mass spectroscopy. The final product of thermal decomposition was determined by X-ray patterns.