The enhancement of heat transfer caused by the presence of a single vortex generator in a laminar boundary layer was experimentally investigated. The local heat transfer coefficients just downstream of the vortex generator and the mean and fluctuation components of velocity were measured. A substantial increase in the heat transfer was noted, with a maximum improvement of the heat transfer coefficient of 80%, even in regions where the laminar structure was clearly predominant. It was observed that the heat transfer coefficient presented two peaks in the spanwise direction. These peaks were found to be associated with the downward motion of the mean vortex and the corner vortex, which arose in the generator's front corner. The influence of the height, angle of attack and geometry of the vortex generator on heat transfer was also investigated.