Drilling process monitoring (DPM) has been rarely adopted in deep rock engineering for structure identification and mechanical property estimation of rock masses. Furthermore, it is difficult to accurately identify complex structures based solely on drilling parameters. To address these issues, we present an integrating method of DPM, borehole televiewer, and Hoek–Brown strength criterion. This method was applied in Jinping deep tunnel with a buried depth of 1900 m and homogeneous lithology. Another comparison test was carried out in Hongtoushan Copper Mine with heterogeneous lithology. The results showed that the drilling speed is sensitive to changes in the rock mass structure. The drilling speed of intact cores (5.26–6.74 cm/min) is the highest, followed by discing cores (5.12–5.85 cm/min) and then jointed cores (3.50–4.62 cm/min). In addition, the drilling speed responses to discing and jointed cores similarly, with sudden change characteristics, which may indicate the location and range of structure planes in the borehole. Finally, the drilling speed response varies according to the surrounding rock conditions. The drilling speed is positively correlated with mechanical properties when the rock mass has a homogeneous lithology and is negatively correlated when the rock mass has a transformed lithological zone. This study provides important support for using DPM to identify the rock mass structure and mechanical properties for deep engineering projects. [ABSTRACT FROM AUTHOR]