The market for flowers and ornamental plants has been growing in Brazil. In this context, sunflower has been increasing its importance mainly as a cut flower. There are cultivars of distinct colors and shapes, but sunflower is a very high flower to be selled in pots. The objective of this research was to evaluate the effect of the growth regulators such as mepiquat chloride and paclobutrazol in the height reduction of the Sunflower known as 'Florenza' to be used it in potted flower. We adopted a completely randomized design in a 2x5 factorial scheme with 11 treatments and ten repetitions. In five samples, the mepiquat chloride (0, 2, 4, 6, 8, 10 L ha ) were applied. The applications were repeated at 15, 30 and 45 days after sowing. The plant height, stem diameter, intern diameter of the main capitulum, number of leaves and capitula, dry mass of leaves, stem, capitula and root, leaf area and chlorophyll content were evaluated. The concentration of 10 L ha -1 of mepiquat chloride was the most effective dose in reducing the height of a red-yellow 'Florenza' sunflower showing a height 43.2 cm smaller than the one from the control treatment.