A series of novel 1-substituted-2-aminobenzimidazole derivatives were synthesized. The structures of the synthesized compounds were confirmed by 1H-NMR spectra and by elemental analysis. Acute toxicities of these compounds were detected on mice via toxicity (logLD50). QSAR analysis of these chemicals was studied on the relationship between acute toxicity and the octanol/water partition coefficient (LogP). The products were identified by the results of elemental analysis and 1H-NMR spectra. The toxicity (logLD50) of 2-aminobenzimidazole 1-substituents were correlated well with the partition coefficient LogP, r=0.9243. The bioactivity (toxicity) of 2-aminobenzimidazoles can be predicted by the molecular structural parameter such as LogP.