<p>The Helishan uplift, which was formed during the late Cretaceous, is the northern boundary of the Jiudong basin. It has played a critical role in controlling basin formation and evolution due to the expansion of the northeastern Tibetan Plateau and therefore hydrocarbon generation, making it a subject of significant research interest. In this study, a north-south-trending MT profile was used to obtain a high-resolution crustal resistivity model beneath the Helishan uplift and its adjacent regions. Beneath the Helishan south fault, a south-dipping, conductive zone extends from the surface to depths exceeding 10 km. This feature is interpreted as a decollement-fracture zone between the Cretaceous strata and the underlying basement, filled with conductive materials. It supports the debated deep south-dipping feature of this fault. Beneath the outcropping Cretaceous strata, a resistive zone dips southward on the southern side and northward on the northern side of the Helishan, respectively, which may represent compacted Cretaceous carbonate rocks or hydrocarbon source rocks in the Jiudong basin. They are suggested to have undergone decoupling and fracturing due to Cenozoic thrust-nappe tectonics, potentially creating space for hydrocarbon generation and storage. On the northern side of the Helishan uplift, a north-dipping, conductive zone is observed beneath the Moshiliang-Jintananshan fault, possibly representing stratigraphic boundary or fracture zone. Together with the south dipping conductive zone beneath the Helishan south fault, these features may jointly represent the two wings of an anticline with opposing dips. The Cretaceous strata, particularly their fractured lower sections, serve as an available space for both hydrocarbon generation and storage. Since the Tertiary, under intense northward thrust-nappe compression from the Qilian Orogenic Belt, these strata have been overlain by conductive cap rocks, jointly controlling hydrocarbon accumulation.</p>