Lactose hydrolysis, a widely employed strategy, involves enzymatic breakdown of lactose into its constituent sugars, glucose and galactose, making dairy products more digestible for lactose-intolerant individuals. This book chapter provides a thorough examination of the various processing parameters affecting lactose hydrolysis, encompassing factors such as temperature, pH, enzyme concentration, substrate concentration and presence of inhibitors. Chapter also deals with the advantages of use of membrane processing and sonication process for lactose hydrolysis. Through a comprehensive review of literature and experimental findings, the intricate interplay between various processing parameters and kinetics of lactose hydrolysis for both free form of enzyme as well as immobilized enzyme over a suitable matrix are elucidated.