Novel 2-substituted 1-alkyl-nitroimidazoles and a process for their preparation by reaction of 2-methyl-nitroimidazoles with oxalic acid diesters, followed by reaction of the resulting nitroimidazol-2-yl-pyruvic acid esters with chlorine, in turn followed, if desired, by reaction of the resulting 2-dihalomethyl-nitroimidazoles with water. Both the novel and the known compounds obtainable by the process of the invention are valuable starting materials for the preparation of dyes, pesticides and drugs.