Investigating the spatiotemporal heterogeneity of livestock environmental efficiency and its decoupling effect is crucial for fostering the coordinated development of livestock economy and environmental sustainability. This study examines the spatiotemporal distribution, regional gaps, dynamic evolution, and decoupling effect of livestock environmental efficiency across 30 provinces in China from 2006 to 2021. By integrating the super-efficiency EBM-DEA model, the GML index, the Theil index, kernel density estimation, and the decoupling model, we provide a comprehensive analysis of the sector’s efficiency dynamics. The findings indicate that while China's livestock environmental efficiency has exhibited an overall upward trend, its absolute level remains relatively low, with a significantly higher number of non-DEA-efficient provinces compared to DEA-efficient ones. The total factor productivity of livestock environmental efficiency has shown continuous improvement, primarily driven by technological progress. The Theil index analysis reveals an uneven regional distribution, with the highest gaps observed in the eastern region (11.93%), followed by the western (10.96%), northeast (8.78%), and central regions (7.37%), with intra-regional gaps being the dominant source of overall gaps. Moreover, provincial gaps in livestock environmental efficiency are substantial and exhibit a polarization trend. During the periods covered by the 11th to 13th Five-Year Plans, the decoupling relationship between livestock environmental efficiency and economic growth predominantly manifested as "strong decoupling," "expansive negative decoupling," and "weak decoupling," with the latter two representing more favorable development states. These findings offer valuable insights for policymakers to optimize regional strategies and enhance the sustainability of the livestock industry.