Countries worldwide are paying increasing attention to the origin, accumulation, and resource potential of helium. The key to understanding helium enrichment and accumulation in various types geological formations lies in the spatial relationships between helium sources and reservoirs. This paper systematically analyzed the characteristics of helium- rich gas reservoirs in diverse tectonic settings worldwide. We measured and summarized uranium and thorium content in main potential helium source rocks and conducted a detailed study of typical helium- rich gas reservoirs in the bauxite strata of the Ordos basin. Our findings indicate that helium in geological formations mainly originates from radiogenic helium of crustal origin and mantle helium. Large- scale helium source rocks, e.g., ancient basement granite/metamorphic rocks with high uranium and thorium content, favorable source- reservoir configuration, and efficient helium migration from source to reservoir, are the key conditions for the formation of large- scale helium- rich gas fields around the world. Helium usually co- accumulates with natural gases such as CH4, CO2, and N2 in oil and gas reservoirs. Helium content shows a positive correlation with N2, suggesting a shared origin, while negative correlations with CO2 and CH4 indicate dilution effects on helium concentration. Based on the source- reservoir relationship, helium- rich gas reservoirs are divided into three types: endogenous, exogenous, and mixed. Endogenous helium reservoirs, which mainly include helium- rich shale gas reservoirs, derive helium from the decay of uranium and thorium contained in the shale itself. Helium and natural gas generated from organic matter in the shale constitute a reservoir with the same source and reservoir. Exogenous helium reservoirs, mainly conventional sandstone and carbonate gas reservoirs, receive helium from crustal helium or mantle helium in the basement outside the gas reservoir. Helium is transported by water or natural gas through faults connecting deep helium sources to uplift areas where it is enriched in a helium- rich gas reservoir. The helium- rich gas reservoir in the bauxite stratum is a mixed helium reservoir. Helium can come from exogenous ancient basement rocks or endogenous bauxite, mud shale, and coal rocks within the bauxite layers. Endogenous and exogenous helium, along with hydrocarbon gas from mudstone or coal source rocks, are jointly enriched and co- accumulated in the bauxite strata, forming a mixed helium reservoir with different sources in the same reservoir.