This study was planned to investigate the Zn and Cu concentration in the blood plasma and feather of laying chicken and to determine the effect of age on the concentration of trace minerals. The Cu and Zn levels of blood plasma and feather were determined by AAS (atomic absorbtion spectrophotometer) in 17., 25. and 35. weeks. Zn and Cu concentrations determined in blood plasma were, 0.23±0.09, 0.39 ±0.07, 0.35 ±0.28 and 1.37±0.15, 2.26±0.59, 2.79± 0.64, and in feather, they were 1.18±0.07, 2.97±0.11, 4.32±1.16 and 156.33±35.63, 166.38±28.18, 187.67±28.19 respectively. As a result, the trace element concentrations were showed differences by weeks. In addition, there was no relationship between trace mineral levels of blood plasma and feather samples.