Hydrazide and their heterocyclic derivatives exhibiting wide range of biological activities. Among different biological activities antimicrobial, antitubercular, antiamoebic and antimalarial are noteworthy. Further, presence of different substituents and derivatization to heterocyclic ring of hydrazide derivatives affect biological outcomes to a great extent. Therefore, researchers have synthesized compounds containing hydrazides and their heterocyclic derivatives with variable substituents as target molecules and evaluated their biological activities. Present review describes the antimicrobial importance of hydrazide derivatives along with their structure activity relationship. Moreover, we have put a light on targets of antimicrobial hydrazide derivatives through which they induce biological effects. Present review will be helpful in designing and structure activity relationship study of bioactive hydrazide derivatives.