The reactions of carbon monoxide with the palladium nitrosoarene complexes Pd2(μ-OCOR)2(—CH2C6H4NO)2 (1, R = Me, CF3, But, or Ph) and Pd2(μ-OCOR)2(PhNC6H4NO)2 (2, R = Me, CF3, But, or Ph) were studied. Complexes 1 contain the o-nitrosotoluene molecule metallated at the methyl group. In complexes 2, the phenyl-o-nitrosophenylamide ligand coordinated via two nitrogen atoms can be considered as a nitrosobenzene derivative bearing the NPh group in the ortho position of the Ph ring. It all cases, carbonylation of the complexes afforded the corresponding aryl isocyanates Ar—N=C=O or the products of their further transformations. The mechanism of reductive carbonylation of nitroarenes catalyzed by palladium compounds and the role of palladium nitrosoarene complexes as possible intermediates in this process are discussed.