To address the key technical challenges in geological core drilling under complex geological conditions at the Zhangfushan mining area, including upper stratum collapse, surface deformation, groundwater drainage-induced borehole wall instability, and dynamic fluid loss during drilling, this study implemented optimized hole structure design combined with casing-while-drilling technology to mitigate borehole instability. Additionally, an innovative pressure-controlled check valve was introduced to regulate the dynamic pressure of drilling fluid, ensuring safe bit penetration through the upper complex formations. In the lower stable strata, a full-hole wireline coring assembly was employed to achieve precise borehole trajectory control, ultimately successfully penetrating the target ore zones. Engineering practices demonstrate that this integrated approach provides technical references for core drilling in similar geological settings and supports new breakthroughs in deep mineral exploration.