Heavy-metal emissions have appeared as one of the most artificial environmental issues, removing of such emissions from environment requires complex physicochemical processes. Therefore, it is essential to control heavy-metal emissions for the pressure alleviation of heave-metal treatment. In this study, inter-regional heavy-metal emission cluster model is developed and employed in Guangdong Province, China to quantify five major heavy metals (i.e. Hg, As, Cd, Cr and Pb) caused by extra-provincial intermediate investment, intermediate use and final consumption. Furthermore, this study fills the gap of previous studies through clustering various provinces based on the similar trade activities characteristics, which helps academics to shed light on the influences caused by different provinces and promote the rationality of heavy-metal policy legislation. Critical provinces are identified from different aspects, which are responsible for the heavy-metal emissions of Guangdong Province, such as Shanxi and Hebei for huge investment, Jiangsu and Zhejiang for huge use and Guangxi and Yunnan for huge final consumption. Among them, extra-province intermediate investment is the largest contributor to the heavy-metal emissions of Guangdong Province. Moreover, different provinces are generally aggregated based on northern, eastern and central of China, revealing that heavy-metal emission impacts from other provinces are geographically diverse. In total, this study puts forward a perspective to assess the influences caused by other provinces on Guangdong Province through investigating extra-provincial impacts from multiple perspectives.