The lattice oxygen mechanism (LOM) plays a critical role in the acidic oxygen evolution reaction (OER) as it provides a more efficient catalytic pathway compared to the conventional adsorption evolution mechanism (AEM). LOM effectively lowers the energy threshold of the reaction and accelerates the reaction rate by exciting the oxygen atoms in the catalyst lattice to directly participate in the OER process. In recent years, with the increase of in-depth understanding of LOM, researchers have developed a variety of iridium (Ir) and ruthenium (Ru)-based catalysts, as well as non-precious metal oxide catalysts, and optimized their performance in acidic OER through different strategies. However, LOM still faces many challenges in practical applications, including the long-term stability of the catalysts, the precise modulation of the active sites, and the application efficiency in real electrolysis systems. Here, we review the application of LOM in acidic OER, analyze its difference with the traditional AEM mechanism and the new oxide pathway mechanism (OPM) mechanism, discuss the experimental and theoretical validation methods of the LOM pathway, and prospect the future development of LOM in electrocatalyst design and energy conversion, aiming to provide fresh perspectives and strategies for solving the current challenges.