Abstract: Fusobacterium nucleatum (Fn) is closely associated with the occurrence and progression of colorectal cancer (CRC). The development of specific antibacterial agents targeting Fn is crucial for the prevention and treatment of CRC. Based on the preliminary phenotypic screening results from our research group, dimetridazole was successfully identified as a hit compound with antibacterial activity against Fn. In this preliminary structural optimization study, we designed and synthesized seven novel nitroimidazole derivatives comprising three structural types, followed by antimicrobial evaluation of all target compounds. Among them, compound CL6 exhibited excellent antibacterial activity against Fn (MIC = 0.5 μg·mL^-1) and demonstrated good selectivity towards intestinal bacteria and normal cells. Compound CL6 significantly inhibited the migration of CRC cells (HCT116) induced by Fn preliminary mechanistic studies suggest that compound CL6 disrupts the integrity of the Fn bacterial biofilm and cell wall, providing a promising lead compound for the development of novel anti-Fn drugs.