Di- and polyamines of the diphenylmethane series are produced by a) converting nitrobenzene and methanol in the presence of a catalyst to aniline, formaldehyde and carbon monoxide, and then b) converting the aniline and formaldehyde produced in step a) in the presence of an acid catalyst to di- and polyamines of the diphenylmethane series, and c) converting the carbon monoxide produced in step a) with chlorine to phosgene.