Asian countries are urbanizing at an unprecedented rate, which has led to significant demand for sand. While sand mining fuels infrastructure development, creates livelihoods, and stimulates local economic activity, it also drives a series of environmental and socio-economic consequences which cannot be ignored. These include erosion, the destruction of habitats and loss of biodiversity, the deterioration of traditional livelihoods, forced displacement of communities, and damage to homes and infrastructure. On the one hand, this thesis uses mixed methods to study the multifaceted impacts of sand mining along the Red River in China, near the Vietnamese border. On the other hand, using qualitative methods, it explores how these impacts unfold along the Mekong River in Cambodia, near Phnom Penh. Using a political ecology approach, it identifies the actors involved in sand mining, their motives, and their impacts on the environment and local communities. The extractivism framework is used to describe sand mining activities and practices. In doing so, this thesis contributes to the literature on the understudied sand mining industry and its far-reaching impacts.