The present invention concerns novel N,N'-diphenyl-N-(N''-alkylcarbamoyl)formamidine derivatives of the formula: Ar1-N=CH-N-Ar2 ?? ??R1 CO-N ANGLE R2 wherein R1 is hydrogen or alkyl, R2 is alkyl and Ar1 and Ar2 are each phenyl or a substituted phenyl, which compounds are useful as herbicides.