Hydrogen electrosorption into Pd-rich (>75 at.% Pd in the bulk) Pd-Pt alloys obtained by electrodeposition was studied in acidic solutions (0.5 M H 2 SO 4 ) using cyclic voltammetry and chronoamperometry. The influence of temperature (in the range between 283 and 328 K) on the amount of absorbed hydrogen, the potential of the ␣- phase transition, the extent of absorption-desorption hysteresis and the potential of absorbed hydrogen oxidation was examined. It has been found that for the temperature range studied the potentials of the ␣ →  and  → ␣ phase transitions are shifted negatively with both increasing temperature and decreasing Pd content in the alloy bulk. Thermodynamic parameters (Gibbs free energy, enthalpy and entropy) of the -phase formation and decomposition were determined. With decreasing Pd bulk content the process of the -phase formation becomes less exothermic and the thermodynamic stability of the -phase decreases. The maximum hydrogen absorption capacity of Pd-Pt alloys decreases with increasing temperature and decreasing Pd bulk content. The potential of absorbed hydrogen oxidation is shifted negatively with increasing temperature and decreasing Pd bulk content.