<p>The relationship between forest biodiversity and ecosystem functions can be significantly affected by human disturbance and climatic conditions. However, it is unclear how these factors affect the relationship between biodiversity and ecosystem multifunctionality (B-EMF), particularly in widely distributed temperate forests. Therefore, this study aims to investigate the mechanisms by which human disturbance, climatic conditions and their interactions affect the B-EMF relationship in our large temperate forest region. Based on a set of forest inventory data, we used structural equation models and multiple linear regression models to explore the main factors influencing the B-EMF relationships. Results show that the species diversity, functional diversity and phylogenetic diversity of woody plants are significantly positive to the ecosystem multifunctionality in the temperate forest region. The effects of species diversity and functional diversity on ecosystem multifunctionality decrease with improved climatic conditions, and human disturbance aggravates the negative effects of climatic conditions. Human disturbance affects ecosystem multifunctionality and the B-EMF relationship by indirectly shaping the woody plant diversity. The findings highlight the important role of human disturbance in mediating the climate-dependence of B-EMF relationships, suggesting that conserving and restoring biodiversity and ecosystem functions in temperate forests can be achieved by controlling human activities amid global climate change.</p>