<p>Global warming has emerged as a key driver of global biodiversity loss, substantially impacting on the geographical distribution and richness patterns of species. <i>Picea</i>, a crucial component of China’s forest ecosystem, plays a vital role in ecological functioning and conservation. This study employed the MaxEnt model and integrated distribution data of 22 <i>Picea</i> species in China to predict historical and future diversity patterns and trends. Additionally, using structural equation modeling (SEM), this study revealed how global warming and environmental heterogeneity drive the richness patterns of <i>Picea</i> species in China, and identified relevant diversity hotspots and conservation gaps. Results showed that climate change contracts suitable habitats for some <i>Picea</i> species and drives most taxa upward to higher latitudes and elevations. Environmental energy and water availability directly control <i>Picea</i> richness, whereas environmental heterogeneity dominates richness spatial patterns via strong indirect effects and the largest total effect. Furthermore, the analysis of protection effectiveness revealed that <i>Picea</i> species are well protected within the existing conservation network; however, certain conservation gaps remain. Notably, hotspot regions distributed in the Hengduan Mountains demand focused attention. This study investigated the response patterns of <i>Picea</i> species diversity in China to global warming and environmental heterogeneity under a multi-climate scenario framework. It not only offers insights into the evolutionary mechanisms underlying the distribution patterns of coniferous forests but also provides a scientific foundation for the strategic planning of biodiversity conservation priority areas in the context of climate change.</p>