Compound dry-hot events (CDH) are escalating climate hazards in China. This study examines spatiotemporal changes in the frequency, duration, dryness severity, and extreme heat characteristics of CDH using highresolution daily data, including the Standardized Precipitation Evapotranspiration Index (SPEI) and daily maximum temperatures, from 1962 to 2022. Using high-resolution daily data (1962-2022) and a conditional Copula-based framework to calculate a risk amplification ratio (RAR), we analyzed daily CDH events nationwide. Our key results show: (1) a significant increase in the frequency and spatial extent of drought-related heatwaves, especially in recent decades; (2) intensifying CDH events, with annual durations extending by 1.8-3.6 days and severity rising by 2-9 units per event; and (3) drought amplifying concurrent heatwave risks by 3-7 times across most regions, which underscored regionally amplified impacts, particularly in China's arid regions, largely driven by anthropogenic climate change. The analysis, further validated by employing two distinct data products, indicates that background aridity critically modulates both CDH spatiotemporal characteristics and the magnitude of drought-induced heatwave risk amplification. By leveraging daily-scale data and a novel probabilistic framework, this research enhances the mechanistic understanding of compound event dynamics and underscores the necessity of accounting for drought as a key triggering factor in climate risk assessments.