Present book entitled 'Insilco studies on Bioactive Heterocycles' describe that it is appropriate to give the brief note about heterocyclic compound bearing benzoimidazole, Urea, Chalcone, benzodiazepines and phenyl hydrazone and its analogues discussions. The structures of all analogs were confirmed by IR, 1H and 13C-NMR, MS spectra and HRMS spectral data. This book also suggested that the synthesized heterocyclic compounds were evaluated for their in vitro antimicrobial activity, anti-inflammatory activity, antioxidant activity and Cytotoxicity. Moreover, structure and biological activity relationship were also further supported by in silico molecular docking studies of all the active compounds were explained. This book is useful for those researchers who are involved to work in such related heterocyclic compounds.