Description of the subject. Tree diversity is essential for maintaining ecological richness and the survival of threatened species. Identifying the factors that favour it is therefore necessary to better guide agricultural policies. Objectives. The aim of this study is to analyse the determinants of tree diversity in the cocoa-growing areas of Côte d'Ivoire Method. The data used come from a survey of 150 cocoa farmers selected in the localities of Bonon, Biankouma and Soubré. These sites were chosen according to an East-West gradient corresponding to the evolution of the cocoa loop in Côte d'Ivoire. Floristic inventories were carried out in the cocoa farms of the selected farmers in order to determine floristic diversity. A Kruskal-Wallis test was performed to compare the farms and multiple linear regression was used to identify the determinants of this diversity. Results. The Biankouma zone has a higher diversity index, both regionally (5.12) and by plot (3.47), compared with the other two zones, the Soubré zone (4.69 regionally and 3.11 by plot) and the Bonon zone (4.22 regionally and 2.98 by plot). This result reflects a decline in floristic diversity as a function of the history of cocoa production. Regression analysis reveals that experience in cocoa production and the density of associated crops have a negative influence on farm diversity. Conversely, the number of associated tree species, the level of education and the distance separating the fields from nearby towns have a positive impact on this diversity. Conclusions. This study recommends promoting agroforestry to diversify cocoa farms. Agroforestry programmes should also focus on farms close to urban centres, to reconcile production goals with biodiversity conservation.