Gums and mucilages are natural polymers with extensive applications in the pharmaceutical industry, particularly as excipients. Their biocompatibility, biodegradability, and natural origin make them ideal candidates for various pharmaceutical formulations. This chapter provides a comprehensive analysis of the structural composition, physicochemical properties, and extraction techniques of plant-derived gums and mucilages. Their functional roles as thickening, gelling, binding, and emulsifying agents in drug delivery systems are critically examined. A comparative evaluation with synthetic polymers highlights their superior sustainability and safety profiles. However, challenges such as variability in physicochemical properties due to environmental factors are also discussed, along with strategies for standardization. Furthermore, recent advancements in modifying these natural polymers to improve their solubility, stability, and bio-adhesion are explored. Special emphasis is given to their emerging applications in novel drug delivery systems, including hydrogels, films, and nanoparticle formulations. This chapter underscores the potential of gums and mucilages as essential excipients in the development of innovative and eco-friendly pharmaceutical products.