This thesis presents a comprehensive review of magnetic Langmuir-Blodgett (LB) films composed of magnetic molecules and ions, exploring their fabrication, properties, and diverse applications. The LB technique is a versatile method for creating organized monolayers with precise control over molecular orientation and thickness, making it highly suitable for the development of advanced magnetic materials. This study aims to reveal the potential of LB technique in fabrication films of various magnetic materials and examining their structural and functional characteristics. Chapter one provides a comprehensive introduction to the Langmuir-Blodgett technique, detailing the monolayer deposition process and highlighting its significance in the fabrication of thin films with tailored properties. This chapter also reviews the applications of magnetic LB films across various fields, including electronics, spintronics and sensing technologies. Furthermore, it discusses the properties and applications of different magnetic molecules used in these films, providing a solid foundation for understanding their functional capabilities. Chapter two delves into LB films that incorporate nonmagnetic molecules and magnetic ions. It analyses the interactions between these components and their influence on the overall magnetic properties of the films. Emphasizing the potential of such composite films in creating novel magnetic materials. Chapter three focuses on LB thin films exhibiting spin crossover phenomena and those films containing radicals alongside other magnetic molecules. Chapter four reviews organic/inorganic hybrid magnetic LB films created by combining magnetic molecules with inorganic components. These hybrid films leverage the advantages of both organic and inorganic materials, resulting in enhanced magnetic properties and stability. This chapter focusing structural configurations, and the resulting magnetic behaviours, highlighting the potential of hybrid films in advanced applications.