Measurements have been made of the value (∂T/∂P)sas a function of pressure up to 32 kbar, at room temperature (296.7 °K), for cerium through its electronic transition at 7.5 kbar. The thermodynamical Gru¨neisen parameter is calculated using the thermodynamic relation &ggr;th=(Bs/T) (∂T/∂P)s, whereBsis the adiabatic bulk modulus. An anomalous increase of &ggr;thin the low‐pressure phase and a rapid decrease after the transition are obtained for cerium.