Concentration of copper, iron, manganese, zinc and cadmium in liver, kidney, testis and uterus of Apodemus flavicollis in relation to sex and locality were investigated. For analysis of the content of these trace elements an AAS method was used. In the organs of A. flavicollis from the area of power station Nováky almost in all cases higher concentration of observed elements than in the organs of animals from the area of nuclear power station Mochovce were detected. The females of A. flavicollis from Nováky locality have shown significantly higher concentration of copper in uterus (p < 0.05) and in kidneys (p < 0.01), higher concentration of iron in kidneys (p < 0.01), higher concentration of zinc in kidneys (p < 0.01) and in liver (p < 0.05) and higher concentration of cadmium in kidneys (p < 0.01) and liver (p < 0.01) in comparison with females from Mochovce locality. A higher level of manganese was recorded (p < 0.01) in kidneys of the females from Mochovce (0.3047 mg.kg-1). A higher concentration of zinc was found in the liver of the males from Nováky area (p < 0.05). On the contrary, there was significantly higher amount of zinc in the testis of A. flavicollis from Mochovce.