Lignin nanoparticles (LNPs) have emerged as promising candidates for enhancing sun protection in cosmetics, offering superior UV-blocking capabilities compared to soluble lignin oligomers. However, the effects of the chemical structures of constituting lignin oligomers in LNPs and the particle size distribution of LNPs need further investigation. Additionally, the raw materials used in these works were mainly technical lignin, whose structures significantly changed during the extraction process, making them unsuitable for studying the structural effect of UV-blocking.