Abstract: The Pearl River Mouth Basin is a large Cenozoic oil and gas-bearing basin on the northern continental margin of the South China Sea, with multiple large and medium-sized oilfield clusters such as Huizhou, Xijiang, and Lufeng already discovered. During the 14^th Five-Year Plan period, further exploration successes were achieved in the shallow-middle conventional fields of the eastern part of the basin, while actively transitioning toward the "four new" (new structural zones, new depressions, new stratigraphic systems, and new types) frontier areas. Facing multiple challenges such as deep layers, deep water, and complex lithology, exploration efforts actively sought breakthroughs, achieving significant theoretical advancements and technological innovations, leading to major exploration results. In deep exploration, addressing issues like "closure fragmentation, rapid reservoir facies change, and oil-gas preservation difficulties" in the Zhu I Depression's deep layers, a new "Composite Marginal Basin Deep Oil and Gas Exploration Theory and Technology System" was innovatively developed, breaking traditional constraints. This led to the discovery of large and medium-sized oilfields such as Huizhou 19-6 and Lufeng South in the deep layers of the Huizhou and Lufeng Depressions, with Huizhou 19-6 being China's first offshore deep-ultradepth clastic rock large-scale integrated oilfield. In deep-water exploration, the innovative "Marginal Core Complex-Rifting Depression Oil and Gas Accumulation Theory" guided the discovery of the Kaipingnan billion-ton oil and gas field, marking China's first deep-water deep-layer billion-ton light oilfield, fully demonstrating the broad prospects of China's deep-water deep-layer exploration. In shallow-middle layer follow-up exploration, breakthroughs were made in addressing oil-gas migration challenges, with innovative models like the "helical three-dimensional migration" guiding a series of followup discoveries around the Xijiang, Huizhou, and Panyu oilfields. In deep-water natural gas exploration, research on deep-water reservoir formation mechanisms and lithological trap formation mechanisms led to commercial or potential commercial discoveries such as the Liwan 4-1 gas field, with Liwan 4-1 representing China's first major breakthrough in the ultra-deepwater carbonate rock exploration field. During the 15th Five-Year Plan period, the Pearl River Mouth Basin (eastern part) will continue to scientifically plan the strategic direction and priorities of oil and gas exploration, focusing on four key exploration areas: enriched Paleogene deep/ultradepth, enriched Neogene shallow-middle lithology, deep-water natural gas, and potential enriched zones. Efforts will accelerate the realization of large-scale oil and gas resource reserves, while actively preparing for the exploration of prospective fields such as buried hills, Mesozoic strata, glutenite，and shale oil, strengthening the resource foundation for high-quality development.

Key words: Pearl River Mouth Basin, exploration progress, deep layer field, deep water field, development direction, the 14^th Five-Year Plan, the 15^th Five-Year Plan