The level of regional population mortality is closely related to the degree of regional socio-economic development. This paper attempts to identify the key socio-economic factors influencing the mortality patterns among China's provincial regions and analyze the mechanisms driving these patterns. We first used the data of the Chinese Seventh Population Census to obtain mortality patterns by age, gender, and urban-rural divided for 31 provincial-level administrative regions. Then, stepwise regression was used to screen out twelve socio-economic indicators affecting mortality patterns, and we employed a functional regression model to analyze the influence of these indicators on mortality probabilities across different age groups. The main findings of this study include: (1) Significant gender and urban-rural disparities are evident in China's regional mortality patterns, affecting nearly all age groups. (2) The substantial marginal impact of socio-economic factors on the mortality pattern generally becomes evident after the age of 45, with less pronounced differences in their impact on early-life mortality patterns. (3) The influence of socio-economic factors on mortality patterns varies across different age groups, suggesting the complexity and heterogeneity of this impact in regional mortality patterns, while also acknowledging certain limitations.