Aims: Due the effect of a transplant routine on the maize plant morphology and population stand, the aim of the experiment was to determine the combined effects of three plant densities and the use of transplant on commercial yield for two sweet maize hybrids. Study Design: Canner ( su1 ) and Butter Sweet ( shrunken-2) hybrids were sown, at the same time, by direct seeded or in plastic plug trays (128 cell tray -1 ) for transplant in middle spring and were grown under 4, 8 and 12 plants m -2 plant densities. Place and Duration of Study: Experiment was conducted at the INTA Balcarce Experimental Station, Argentina (37° 45 ′ S, 58° 18 ′ W) during the 2005-2006 and repeated during 2006-2007 growing seasons. Methodology: Plants from direct-seeded or transplant were grown at three plant densities under a field environment. A randomized complete factorial design with three blocks was used. Results: Results showed that transplant increase light interception and radiation use efficiency; the changes in dry weight accumulation in behalf of ears determine an increase in harvest index and yield plant -1 . An increase in plant density at 12 plants m -2 would let to obtain an increase in yield ha -1