In this study, the effects of boundary layer heating, as a means of an active flow control, of the flow over a flat plate on boundary layer transition and aerodynamic performance are numerically investigated. Two-dimensional and three-dimensional CFD simulations are carried out using ANSYS-Fluent software for isothermal, full heating and discrete heating cases. The effects of the free stream turbulence intensity Tu, the surface temperature T-w and the heating section length zeta, being selected as design and flow parameters on boundary layer transition, skin friction coefficient C-f and Nusselt number Nu are parametrically investigated. Simulation results revealed that Tu has a significant effect on the laminar to turbulent transition, and the location of the heater strips has a great importance for discrete heating cases. It is also shown that as compared to full heating of the plate, the discrete heating from the leading edge is more convenient for the low values of free stream turbulence intensities, and the heating may be used as an alternative method for reducing C-f.