This paper systematically investigates synaesthetic metaphors in Mid-Ancient Chinese using a combined approach of quantitative and qualitative analysis. In addition to the previously generalized mapping model, the study identifies several key findings. Notably, vision-related synaesthetic metaphors appear fully developed, while those involving taste and touch remain underdeveloped. Furthermore, no evidence of reverse mappings exists between auditory and olfactory senses. The synaesthetic metaphors in Buddhist sutras are shaped by a negative perception of unclean touch and an emphasis on the dissemination of “vocal education”, leading to an avoidance of tactile imagery. Additionally, auditory perception in these metaphors is characterized by a diverse range of sources and pathways. Regarding production patterns, the dominant form involves two identical sensory combinations being mapped to other senses. These three features reveal significant differences from those found in Chinese literary works.