New substituted carbamoylimidazole derivatives of the general formula (I) ##STR1## have been prepared by reacting the appropriate substituted imidazole derivatives of the general formula (II) ##STR2## with isocyanate compounds of the general formula (III)R.sub.4 -- N .dbd. C .dbd. O (III).the new compounds of the general formula (I) are potent herbicides and fungicides.In the above formulaeR.sub.1 stands for hydrogen atom or methyl group,R.sub.2 and R.sub.3 each may represent a hydrogen atom or a nitro group, or R.sub.2 and R.sub.3 may form together a --CH.dbd.--CH--CH.dbd.CH--group, which forms a six-membered ring together with the adjacent carbon atoms of the imidazole ring, andR.sub.4 stands for a cyclohexyl, phenyl, chlorophenyl or dichlorophenyl group.