Human poisoning with plants is uncommon as often people only eat material known to be non-toxic. In times of food shortage, people are willing to experiment with new plant material such as roots, fruits and mushrooms and this often leads to poisoning. Cooking, a common practice' among humans, often destroys plant poisons. Poisonous plants which cause acute and sub-acute poisoning are well known to the local community where they grow, as the cause-effect relationship is easy to establish, unlike those that cause chronic toxicity. Herbal medicine may cause poisoning, but this is rare particularly among experienced practitioners of herbal medicine. In this article several known poisonous plants in Kenya are briefly discussed.