Aphids are serious pests of the potato crop, notably because they vector numerous viruses. As chemical control is unsustainable and as demand for environmental friendly products is consistently expanding, alternative and sustainable methods of crop protection have to be developed. A promising way consists of using the high genetic potential of wild Solanum accessions. Wild resistant traits in the cultivated potato Solanum tuberosum may allow creation of new resistant cultivars. After quantifying the resistance level of 8 accessions (5 wild Solanum species) against Myzus persicae and Macrosiphum euphorbiae, behavioral experiments were carried out to determine the type of resistance (antixenosis or antibiosis). An olfactory approach ruled out the possibility that wild Solanum species plant volatiles may contribute to the high resistance expressed. In contrast, resistance factors were determined in several plant tissues (surface-cuticle, epidermis-mesophyll, phloem) according to aphid feeding behavior by means of electropenetrographic experiments. Antixenosis resistance (disruption of feeding behavior and plant acceptance) was determined on all accessions against M. persicae and on 4 out 8 accessions against M. euphorbiae. Only one accession exhibited antibiosis resistance (no behavioral disruption but physiological disturbances) against M. euphorbiae. According to resistance type and its localization in plant tissues, several hypothesis are discussed on compounds or mechanisms implied.