Abstract: Marine-continental transitional (MCT) shale gas is an important successor of unconventional natural gas resources in China. Based on integrated analyses of literature review, outcrop investigation, exploration practice, drilling cores, and experimental testing, we systematically reviewed and compared the development history of shale gas globally and in China, examined the exploration progress and challenges of MCT shale gas in the Ordos basin, Sichuan basin, and adjacent areas, and conducted a comprehensive discussion of the key geological conditions for the formation of shale gas and its resource potential, challenges, and counter measures. The results show that MCT shale in China is mainly developed within the CarboniferousPermian strata (Benxi, Shanxi, and Longtan formations), dominated by lagoon, swamp, and tidal flat facies, and possesses favorable conditions for shale gas formation and development potential: (1) The organic-rich shale intervals are thick and widespread, with dominant Type III organic matter, high organic matter abundance (average TOC content≥3.0%), and moderate thermal maturity (R_o=1.60%-2.61%), which are conducive to large-scale gaseous hydrocarbon generation. (2) Shale reservoirs are dominated by inorganic pores (clay mineral pores), with well-developed organic micropores (0.4-0.7 nm), and a high proportion of adsorbed gas (average 61.0%, up to 75%), providing favorable conditions for shale gas storage and enrichment. (3) The total MCT shale gas resource in China exceeds 50×10¹² m³, of which the favorable resource volume in the Jinci Member of the Benxi Formation, the Shan₂³ and Shan ₂²⁺¹ sub-members of the Shanxi Formation in the Ordos basin reaches 16×10¹² m³. Notably, a commercial breakthrough has been achieved in the Shan₂³ sub-member, demonstrating promising exploration and development prospects. However, the exploration and development of MCT shale gas remain at the early breakthrough stage, facing many challenges such as strong heterogeneity of sweet spots and high clay mineral content, which constrain drilling, completion, fracturing, and development effectiveness. To achieve large-scale development of MCT shale gas requires integrated evaluation of“sedimentary facies-preservation conditions–resource potential,”as well as technological advances in“multi-cluster within stage+limited-entry fracturing” and “platform-based well pattern+3D well deployment.” This will promote the coordinated co-production of shale gas, coal-rock gas, and tight gas within the MCT shale system in the context of the whole petroleum system. By overcoming bottlenecks in geological theory and engineering technology, MCT shale gas is expected to become a new strategic successor for increasing natural gas reserves and production in China.