Locally in the context of care and prevention of malnutrition, in Niger, communities use plants. The general objective aimed at through this study is to inventory and ofto map the plants used in children under 5 in the Mayahi department of Niger. To do this, an ethnobotanical survey was carried out on 100 women, mothers / grandmothers aged 35 or older and 23 traditional / retailers, all over 50 years of age. This study shows that 15 families of plants used left century in 23 genera and 24 species have been recorded. These plants are used either to treat children with diarrhea or to stimulate children 's appetite for better growth. The most commonly used is the family of Euphorbiaceae (4 species) with a proportion of 15 4%, followed by the family of Mimosaceae (3 species) and Caesalpiniaceae (3species) with a proportion of 11.5% each. The bark is the most used part (46.4%).The most used form is the plant powder (70.9%).Note that the use of these geographical map your differs from one municipality to another. The diversity of properties and indications, the various organs used as well as the methods of preparation and administration, testify to a good knowledge of the plant diversity of Tradipraticiens and mothers of children. However, biological and chemical tests will verify the veracity of the therapeutic indications received for an extension as an alternative for the prevention of moderate acute malnutrition in children under 5 years of age .