A series of benzimidazole derivatives carrying different heterocycles such as 1,2,3-thiadiazole, 1,3,4-thiadiazole, thiazolidine, 2,3-dihydro-thiazole, 1,3,4-oxadiazole, semicarbazone and substituted thiosemi-carbazones were synthesized. Also a series of 1-methylbenzimidazole carrying hydroxy ethyl-amide, substituted sulfonyl hydrazide and benzoyl hydrazide from aminobenzoyl group at position 2 of 1-methylbenzimidazole were synthesized. The antimicrobial evaluation of some of the new compounds was carried out.