In a context where sustainable and environmentally friendly materials are increasingly in demand, natural fibre reinforced composites appear to be a promising alternative in the field of construction and engineering materials. This chapter presents a comprehensive literature review on the use of sisal fibres as a natural reinforcement in gypsum-based materials. Sisal fibres, derived from the Agave sisalana, are characterised by good mechanical properties, biodegradability and abundant availability, especially in Morocco. Gypsum, on the other hand, is a widely used building material valued for its thermal and acoustic insulation properties, fire resistance and ease of processing. This study examines the physical, chemical, mechanical and thermal properties of sisal fibres, as well as the characteristics of gypsum and the techniques used to extract the plant fibres. The performance of natural gypsum fibre composites is also discussed. Taken together, the results highlight the potential of sisal-gypsum biocomposites as an alternative to conventional materials due to their low environmental impact and satisfactory mechanical behaviour. This work thus provides a scientific basis for future experimental research aimed at optimising the formulation and performance of this sustainable composite system.