<p>Plant cell walls contain lignin, a complex organic polymer regarded as a good substrate for various value-added products in industries. Lignin may be utilized in synthesizing green nanomaterials, which have superior properties to the parent polymers. Lignin nanoparticles (LNPs) are nano-sized biopolymers derived from lignin and have gained interest among researchers due to their distinctive qualities and wide range of uses. Several methods, divided into physical, chemical, and biological, can be employed to synthesize lignin nanoparticles from different lignin sources. As a result, their morphology, shape, size, yield, and stability will vary. LNPs have potential uses in the environmental, biomedical, agricultural, pharmaceutical, and other industries. The advancement of novel nano-lignin products and further investigation into nano-lignin can be enhanced through a thorough analysis of its preparation methods and application status. This holds considerable importance for the utilization of lignin and its sustainable development. Recent innovations in synthesizing lignin nanoparticles are thoroughly discussed in this review. The application of LNPs in various fields, challenges, and future perspectives are also discussed.</p>