Livestock poisoning by plants is one of the serious causes of economic loss to the livestock industry. Veterinarians and animal owners are frequently confronted with the task of determining whether or not a plant is responsible for poisoning of animals. Similarly the presence of plants other than grasses in a pasture is always a concern to livestock owners. Ingestion of many plants produces non-specific clinical signs that must be differentiated from other disease conditions. In addition, death due to toxic plant ingestion often does not result in characteristic post-mortem lesions. Unfortunately, relatively few laboratory tests are available to detect plant toxins in either ante-mortem or post-mortem samples. Making a definitive diagnosis of plant poisoning is difficult. It is important to be familiar with the poisonous plants growing in the specific area and the conditions under which animals may be poisoned. Hence, the pathology of plant poisonings in animals is necessary to be studied for proper management, treatment, prevention and control of plant poisoning cases.