Wild and cultivated tomato types were screened by mechanical inoculation, for resistance to strains of the potato virus Y complex common in tomato plantings in the State of São Paulo, Brazil. Out of 60 types tested, immunity to virus Y was found in Lycopersicon peruvianum var. detatum (P. I. 128660) and L. peruvianumvar. humifusum (P. I. 127829); a satisfactory resistance level was found in L. pimpinellifolium NAV 1062 and in an introduction from Peru (P. I. 126410). Difficulties were encountered in obtaining viable hybrids between the immune source plants (Lycopersicon peruvianum) and the cultivated tomato varieties. This fact prevented the study of the inheritance of immunity to virus Y in tomato and its incorporation to cultivated types. The behavior crosses, and from backcrosses between Lycopersicon pimpinellifolium NAV 1062, P. I. 126410, and the commercial variety Santa Cruz indicated that the high level of resistance of the first two types to strains of the Y virus is conditioned by the same pair of recessive genes. Progenies derived from the cross Santa Cruz x P. I. 126410 were more promising than those from the cross Santa Cruz x Lycopersicon pimpinellifolium NAV 1062. Selections made in advanced generations of the former cross followed or not by backcrossing originated 3 groups of progenies. These tomato plants possess commercial characteristics comparable to those of the Santa Cruz variety and incorporate a satisfactory level of resistance to strains of the Y virus. One of the lines selected was named Ângela and is being released to growers for large scale testing.