The heterocyclic ring system is the important part of the most biologically active drug molecules. Heteroaromatic rings are essential because of similarity with respect to the biologically active compounds in the animal Body which include acids, hormones, neurotransmitters, which constitute one or the other Heteroaromatic ring. Many Heteroaromatic rings present, fused, and pendent benzimidazole are also different features of many pharmaceutical products. Among such important benzimidazole have occupied an important place in medicinal chemistry. The benzimidazole as a chemotherapeutic agent was realized when in 1950 it was found that 5, 6- dimethyl-1- D-ribofuranosyl benzimidazole was an integral part of the structure of Vitamin B12 and other drugs. Benzimidazole derivatives possess a broad spectrum of biological activities, ranging from widely used human and anthelmintic activity to anticancer properties.