Résumé : Introduction: Women's dietary habits are very important due to the specific nutritional requirements for reproduction. This study aimed to describe women's dietary habits during pregnancy and breastfeeding and to identify factors influencing these habits. Methods: We conducted a qualitative study of pregnant and breastfeeding women living in Amoron'i Mania region, Madagascar. Eight focus groups (6-10 women per group) and 23 individual interviews were carried out to collect data. Thematic analysis was used and focused on the description of women's dietary habits on the basis of dietary behaviours as well as of sociocultural and economic determinants of the described habits. Results: During pregnancy and breastfeeding, women's dietary habits did not vary considerably except at the very beginning of breastfeeding. They had a little diversified and monotonous diet, poor in fruit and vegetables and poor in proteins. At the very beginning of breastfeeding, during the practice of "mifana" tradition, women had a diet more rich than usual. These dietary habits were influenced by the type of agricultural products in the region and by their availability during the year (self-consumption)as well as by purchasing power (in case of shortage) and tradition. Conclusion: Mothers' dietary habits appear to be inadequate. This study highlights the importance of improving knowledge of the determinants of mothers' dietary behaviours.