The invention relates to a process for regenerating a catalyst used in the decarbonylation of an aldehyde, wherein the catalyst is a heterogeneous, supported catalyst containing a metal selected from the group consisting of Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt and mixtures thereof, and wherein the catalyst is subjected to a gas stream comprising hydrogen at a temperature of from 200 to 600° C., wherein substantially no oxygen is used in the regeneration process.