In Algeria, tomato cultivation under glass and in open fields has suffered considerable damage following the introduction of a new pest, Tuta absoluta. Our work is being carried out at the I.T.D.A.S in Hassi Ben Abdellah (Ouargla), with the aim of determining the effectiveness of tomato variety resistance to Tuta absoluta. ANOVAs carried out on morphological and developmental parameters showed that the six varieties were more or less identical, with the exception of the LUSSAN variety, which stood out from the others on account of its height and growth rate, and the ZAHRA variety, which was characterized by a considerable number of leaves at the end of cultivation. In terms of production parameters, SALINERO and ZAHRA were the most productive varieties in terms of number of fruits and average weight. With regard to estimated damage and losses, statistical analyses show that all varieties, without exception, were infested by Tuta absoluta at very high rates from the 4th month of planting, until total annihilation of the plants at the end of the crop.