Sonochemistry has emerged as a promising technology for the synthesis of organic compounds along with inorganic nanomaterials. It promoted the reaction in homogenous and heterogeneous mediums with excellent product outcomes and remarkable selectivities. This method catalyzes the reactions in the absence of the catalyst through the cavitation effects via the formation of ionic or radical intermediates as primary effects, and mechanical effects resulting from the cavitation are termed secondary effects. This book chapter discusses the various types of sonochemical reactions, mechanisms and reactivity of ultrasound irradiation and its applications in nanomaterial preparations. The advantages of ultrasound-assisted synthesis compared to conventional methods were critically analyzed.