Malai Pandaram tribes are well known for their nomadic way of life style and inherited wisdom of ethnobiology. An ethnobiological survey for Piscicidal plants used by Malai Pandarams has been conducted during 2013 March to 2015 March in the Achankovil River basin. Information on piscicidal plants and their usage were collected through observation, personal conversation and structured questionnaires among them. 41 plant species belonging to 33 genera and 18 families were found of piscicidal value. The plant species are enumerated in alphabetical order along with families and local names, followed by their ethnobiological uses.