Abstract : Preterm infants receive inadequate sensory stimulations during a critical period of brain development. Touch seems to be a key modality in preterm infants. The aim of this thesis was to investigate early manual abilities in preterm infants. Therefore, we focused on manual haptic processing of object shape without vision control. This field of research remained hitherto unexplored in preterm infants. The first study investigated the abilities (intra-manual) to perceive in one hand the difference between the shape of two objects (prism vs. cylinder) in preterm infants from 33 to 34+6 GW (Gestational Weeks). In a second study, we examined the development of these manual abilities depending on the degree of prematurity (three groups). Finally, in a third study, we investigated the abilities (inter-manual) of preterm infants from 33 to 34+6 GW to perceive and memorize an object's shape with one hand and to detect differences between two shapes in the opposite hand. Our results reveal that manual habituation and discrimination of object shape are present in preterm infants from 28 GW. In addition, preterm infants from 28 to 34 GW show recognition memory after haptic interference (presentation of a novel object) contrary to infants from 34 GW. This last result indicates qualitative differences between groups of prematurity. However, our results show no quantitative difference in manual performance between the three groups of prematurity. Finally, results reveal that an inter-manual transfer of shape information is present in preterm infants at 33 GW demonstrating the existence of communication between the two cerebral hemispheres. Overall, our results show that the preterm infant is already endowed with early tactile abilities. This thesis provides new theoretical insights concerning the development of tactile perception and opens new perspectives in the context of developmental care.