In presence of hydrogen, crack-induced hydride formation can occur in specific metallic structures, reduce their mechanical properties and facilitate failure. Phase boundaries have been observed to be preferential site for hydride formation. The inevitable presence of both cracks and phase boundaries is consequently a threat for these metals. This paper presents a phase field approach describing hydride formation induced by a crack lying near a grain boundary, by using Allen-Cahn’s formulation associated with linear elastic fracture mechanics. The analysis of the results reveals an enhancement of crack-induced hydride development in the proximity of a grain boundary.