Among the plant species occuring naturally in Poland, apart from edible and completely harmless to humans, there are also poisonous ones. Without specific knowledge it is not easy to recognize and distinguish them. To make it even more difficult, those plants are able to develop visually tempting fruits. Such species are the topic of this article.Plants are toxic due to the poisons they contain. Toxicity is therefore a natural method of defense against being eaten, which directly affects the survivability of species. Sometimes slight contact with a toxic plant is enough to feel detrimental consequences. In terms of the structure, toxins belong to various organic compound groups, e.g. glycosides, alkaloids or they can be derivatives of certain organic compounds. Some of them are harmful even in tiny amounts, like in a yew’s case, others- in small doses are herbal medicines known for centuries (as black elder or lily of the valley) and wreak havoc in human organisms after overdosing.