ABSTRACT The quality parameters of cassava roots vary between cultivars and depend on abiotic factors, such as plant nutrition. However, the magnitude of how these factors interfere is not yet well defined, especially for phosphorus (P), which is a nutrient directly linked to the synthesis of sugars and starches in plants. Thus, the objective of the research was to evaluate the quality of roots of table cassava cultivars fertilized with doses of P in the Brazilian semiarid. The research was carried out at the Rafael Fernandes experimental farm, Mossoró, RN, Brazil, from June 2018 to April 2019. The experimental design used was in randomized blocks, arranged in subdivided plots and with four replications. Doses of P (0, 60, 120, 180 and 240 kg ha-1 of P2O5) were applied in the plots, and in the subplots, the table cassava cultivars (Água Morna, BRS Gema de Ovo, Recife and Venâncio). Firmness, elasticity, titratable acidity, soluble solids, total soluble sugars, starch and cooking were all evaluated. The quality of table cassava roots varied depending on the cultivar and the dose of P. Doses of P between 120 and 240 kg ha-1 of P2O5 increase the starch content and reduce the cooking time of table cassava roots.