<p>In light of global environmental concerns and the increasing focus on renewable resources, there has been a significant effort to develop eco-friendly and biodegradable materials for the next generation of composite products. The utilization of natural materials in composites has reduced greenhouse gas emissions and the carbon footprint of composites. Despite the advantages of green materials, there are challenges associated with their use, such as poor compatibility between natural fibers and the matrix, as well as the relatively high moisture absorption of natural fibers. Green composites have the potential to serve as a viable alternative to petroleum-based materials, but several issues need to be addressed, including poor interfacial adhesion, moisture absorption, poor fire resistance, low impact strength, and low durability. Numerous researchers have explored the properties of natural fiber composites and have developed various procedures for modifying natural fibers. The aim of this review is to discuss the different treatment methods used in modifying natural fibers for biopolymers and biocomposites production, with specific focus on how they affect the surface morphology and performance of the final products. This comprehensive review of natural fiber properties and treatment effects is crucial for developing novel sustainable and green biomaterials with improved properties for different applications.</p>