This paper examines the relationship between sorcery and envy, focusing on the Kalis of Borneo. According to Kazuyoshi SUGAWARA, envy is permitted within the action space of baboons and chimpanzees, as well as human beings. SUGAWARA argues that envy appears automatically without body expression (including speech action) away from the action space, if sorcery as a cultural device exists in human society. Based on this theoretical orientation, this paper focuses on situations in which envy automatically appears in Kalis society : a village gathering to seek out sorcerers and a ritual setting for treating a sick person suffering from poisoning (a kind of sorcery). Kalis people, however, feel envy is omnipresent in their society. The Kalis attempt to extract part of envy, by explaining misfortune with sorcery or dealing with misfortune in a ritual setting. They believe envy never transforms itself into goodwill or friendliness. Envy, therefore, should be broken into pieces so as not to generate another victim of sorcery. Such practices perpetuate sorcery as a cultural device. ln this sense, sorcery and envy reflexively intensify each other. As shown in this paper, the evolutional theory of emotion will help develop anthropological study on magic, sorcery and misfortune.