Ecoterrorism is a form of sabotage intended to hinder activities that the ecoterrorist considers harmful to the environment. Ecoterrorists belong to the Direct Action school of thought. An example of ecoterrorism is the destruction of tree felling equipment (e.g. spoiling fuel). Radical ecoterrorists sometimes engage in tree-spiking, a practice which can endanger the life of the treecutter.

Another form of ecoterrorism is political, intended to damage an enemy's natural environment. A common example is the military practice of burning conquered lands.