We have studied the magnetocaloric effect (MCE) in GdRu2Ge2 by means of measurements of temperature and field dependence of the specific heat and the magnetization. Two anomalies were observed at T1=29 K and T2=32 K in the zero-field specific-heat curve. Magnetization measurements showed that the magnetic moments of the Gd ions order antiferromagnetically below T2 and follow the Curie–Weiss Law above T2. The magnetic measurements also showed that there exists a field-induced antiferromagnetic to ferromagnetic transition below T1. The magnetocaloric properties estimated from the magnetization measurements by means of the thermodynamic Maxwell relation are in good agreement with those obtained from the specific-heat measurements. The largest observed adiabatic temperature change, ΔTad, is approximately 10 K for a field change from 0 to 15 T. The considerably large magnetic entropy change is due to the field-induced magnetic phase transition, which is magnetically reversible.