With the objective to study the course of absorption of the macronutrients by the rape (Brassica napus) in function of the age of the plant, it was installed one experiment in the experimental field of the Department of Agriculture and Horticulture of Escola Superior de Agricultura "Luiz de Queiroz", USP, in Piracicaba , SP. It was determined the curve of growth of the plant in function of the age, the increase, the concentration and the export of nutrients in the strains 1504 and 1530. The experiment was lead in the agricultural year of 1980, in conditions of field, in Terra Roxa Estruturada soil. After each sample the plants were separated in roots, stalk, leaf, floweres, pods and seeds and analysed for nitrogen, phosphorus, potassium, calcium, magnesium and sulfur. The authors concluded: - The maximum point of development of the plant and production of dry matter is reached to 142 and 179 days after the emergence, for the strains 1504 and 1530, respectively. - The concentration of the macronutrients reduce with the increase of the amount of dry matter, showing one dilution effect. - The increase of the macronutrients maximum increase reached in the end of flowering between 120 and 139 days, for the two strains. - The order of absorption of nutrients is the following: K > N > Cu > S > P > Mg. - The order of export of the nutrients by the grains is: N > P > K = Ca > S > Mg.