Although silicon is not considered an essential element, in some crops such as soybeans, its supply can stimulate plant development and plant production. The growth of soybean cultivars in Cerrado soil subjected to the application of silicon doses was studied. The experiment was conducted in a greenhouse at the Instituto Federal do Amapá - IFAP/Campus Agrícola Porto Grande. The experimental design was completely randomized, arranged in a 5x2 factorial scheme, with four replications. The factors consisted of the control treatment (without Si) and four doses of Si (250, 500, 750 and 1000 mg pot-1 of SiO2), and two soybean cultivars (BRS Tracajá and FTS Paragominas). Growth variables were analyzed, such as: plant height, stem diameter; and dry matter of shoots and roots. Silicon influenced the increase in height when evaluating the cultivars and isolated doses, the same behavior was observed in the dry matter production of the aerial part and total. The element silicon helps in the improvement and gain in height and other evaluated agronomic characteristics, but studies with this element must be more applied, to obtain the answer for other variables and study conditions.