<p>This study presents a comprehensive geochemical and mineralogical characterization of Carboniferous-Triassic shales in Peninsular Malaysia, with a focus on the Gua Musang, Telong, Kepis, Bera, and Kati formations. The research aims to assess their hydrocarbon generation potential and depositional environments through an integrated approach that includes field studies, total organic carbon (TOC) analysis, Rock-Eval pyrolysis, vitrinite reflectance (R_o) analysis, X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). The results reveal varying organic richness and thermal maturity across formations, with the Kepis and Telong Formations exhibiting relatively higher TOC values, indicating moderate hydrocarbon potential. However, most formations show low organic matter richness and a predominance of gas-prone kerogen, suggesting limited commercial hydrocarbon potential. The thermal maturity assessment indicates that the Telong Formation has reached peak oil maturity, while the Kepis and Bera Formations are in the late oil window. In contrast, the Gua Musang Formation remains largely immature. Rock-Eval pyrolysis results suggest that most formations contain Type III kerogen, which is primarily gas-prone. The mineralogical analysis highlights the dominance of illite, kaolinite, and feldspars across all formations, with variations in quartz and calcite concentrations, suggesting different degrees of diagenetic alteration and depositional influences. The XRD and SEM analyses further confirm that these shales were deposited in a deep marine environment, characterized by hemipelagic sedimentation, turbidity currents, and mass transport deposits. This study’s findings help enhance the understanding of the stratigraphic framework and depositional history of Carboniferous-Triassic shales in Peninsular Malaysia. While the shales examined exhibit some hydrocarbon generation potential, particularly in the Telong and Kepis Formations, their overall organic richness and thermal maturity constraints limit their economic viability for hydrocarbon exploration. Future studies incorporating additional geochemical proxies and basin modeling techniques could further refine our understanding of the hydrocarbon system and its potential for unconventional resource exploration.</p>