Oxidation catalyst for diesel engine

An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emis-sions from a diesel engine are described. More particularly, described is an oxidation catalyst composite including a first oxidation material comprising a first refractory metal oxide support, a rare earth oxide, and palladium (Pd); a second oxidation material comprising a second refractory metal oxide, and platinum (Pt) and palladium (Pd); and a protective overlayer comprising a third refractory metal oxide, platinum (Pt) and, optionally, palladium (Pd), and a molecular sieve promoted with a metal selected from one or more of Cu, Fe, Co, Ni, Mn, V, and, Ag. The oxid-ation catalyst composite is sulfur tolerant.