The defect levels in Hg 1 x Cd x Te( x =0.6)n on p junction photodiodes were studied by using the admittance spectroscopy. Measurements identified a hole trap located at 0.15eV above the valence band. The trap density and majority carrier capture cross section were given, with results suggecting hole capture at a neutral trapping center. It was estimated as a Hg vacancy or some composite defects related with it. The minority lifetime of the devices and the product R 0A of area times the dynamic resistance at zero bias were calculated and the results were discussed, too.