Abstract: Deep conglomerate reservoirs are developed in the Jiamuhe Formation of the Zhongguai Uplift, Junggar Basin, and are generally characterized by low mud content, abundant zeolite cement, and strong heterogeneity. Based on core observations, thin-section petrography, reservoir physical property analyses, and fluid inclusion tests, a comprehensive investigation was conducted on pore types, diagenetic modifications, and hydrocarbon charging characteristics of the Jiamuhe Formation conglomerates in the Zhongguai Uplift. The results indicate that the formation and evolution of these conglomerate reservoirs are jointly controlled by sedimentary architecture, diagenetic alteration, and hydrocarbon charging processes, which are manifested in three aspects. First, the large clast size and rapid sedimentation rates significantly weakened mechanical compaction during early burial, providing a favorable material basis for the preservation of primary intergranular pores. Second, variations in source-rock lithology and depositional microfacies are key factors controlling reservoir heterogeneity; abundant supply of basic andesitic rocks from the provenance area facilitated extensive precipitation of zeolite cements. Third, the combined contribution from multiple source rocks and the sustained alteration of conglomerates by multi-stage organic acids created favorable reservoir conditions for hydrocarbon accumulation in the full-sag conglomerates of the Jiamuhe Formation. Overall, the formation of conglomerate hydrocarbon reservoirs in the Jiamuhe Formation of the Zhongguai Uplift is interpreted as the result of coupled evolution between near-source, high-energy depositional processes under a fault–sag transition setting and subsequent diagenetic–accumulation processes. The results provide valuable insights for the study and development of deep conglomerate reservoirs in the Junggar Basin.