The EPR studies have been carried out on gamma irradiated samples of Pd(ClO₄)₂ in 9 M/4 M HClO₄ in the presence and absence of isopropanol [i-PrOH (5%, v/v)], in the temperature range of 77–300 K. The EPR studies revealed the formation of Pd⁺complex, Pd³⁺ complex and several radicals such as H^•,OH^•, ClO₃^•, ClO₄^•and O₃⁻on radiolysis of these systems. Reduction of Pd²⁺to Pd clusters could not be observed in the absence of i-PrOH and warming of the irradiated sample finally resulted in recovery of Pd²⁺ complex. However, in the presence of 5% i-PrOH, strongly oxidizing radicals like OH^•, ClO₃^•and ClO₄^•are suppressed and (CH₃)₂C^•OH radical was produced along with reducing species like H^•. EPR spectra in these strongly reducing conditions showed formation of Pd⁺ complex, which on heating above 230 K, disproportionated into Pd0and Pd²⁺complex and finally lead to formation of Pd metal aggregates. Simultaneously, pulse radiolysis technique has been employed as an alternative method to verify the EPR observations.