Animals experience a great variety of stimuli during their lifetime and rely on perceptual representations in much of their interaction with the world. The perception domestic animals have of humans is of major importance to build and maintain a harmonious human/animal relationship. In this study, we hypothesized that using a primary positive reinforcement in horse training could influence the way horses perceive humans. Thus, we trained 23 yearlings to remain immobile and accept various handling procedures (brushing, feet picking…) on vocal command, giving half of them a food reward (positive reinforcement group, NPR=11) whenever they responded correctly to the command (i.e. remained immobile throughout the handling procedure), while the other half (control group, NC=12) was never given any reward. Results showed that using positive reinforcement during training induces long term positive representation of humans, for young horses trained to obey a vocal command with food as a reinforcement sought and accepted more contact than controls, both with the familiar trainer and with a non familiar person, even several months after completion of training (at least 6 months later).