The article delves into the significance of fluorine modification on TiO2 as a photocatalyst for hydrogen production. Researchers have shown interest in enhancing the photocatalytic activity of TiO2 by overcoming rapid carrier recombination through fluorine modification. The paper discusses the effectiveness of surface adsorbed fluorination and lattice-doped fluorination in improving the functional performance of TiO2. By modulating the surface chemical attributes and electronic configuration of TiO2, fluorine modification has been proven to amplify its photocatalytic performance. The study also explores the impact of fluorine atoms coordinated with different titanium atoms on TiO2. Characterization techniques like X-ray photoelectron spectroscopy and solid-state nuclear magnetic resonance are utilized to understand the modified TiO2 structures. Overall, the article provides a comprehensive review of various aspects of fluorine-modified TiO2, offering valuable insights into its classification, characterization, and mechanistic impact on enhancing photocatalytic hydrogen production performance.