The aim of this work was to investigate the role of sensory information (kinesthetic and visual) and of posture (observer seated or supine) during a judgement of inclination. In the first experiment, we measured the accuracy of the judgement of inclination in a kinesthetic task as a function of posture. The results showed more accuracy in the seated posture. Therefore it seems that changes of the proprioceptive information as a function of posture can affect the kinesthetic sensitivity and than accuracy. In the second experiment, the adjustment task was performed in a visually structured environment. The results showed no significant difference in the accuracy between the seated and the supine posture conditions. We tentatively conclude that the visual information is more relevant than the proprioceptive inputs to determine the accuracy of the judgement of inclination.