Lettuce mosaic virusis the major virus in lettuce (Lactuca sativaL.) in Brazil, causing symptoms of mosaic, vein clearing, necrosis, leaf distortion and growth reduction. The LMV is transmitted by seeds at a rate of 1% to 16%, mostly due to interaction between the isolates LMV-Most and LMV-Common and the lettuce cultivar. In this study, LMV detection by PTA-ELISA in seeds and seedlings of eight lettuce genotypes, ‘Vanessa Roxa’, ‘Baba de Verão’, ‘Verdinha’, ‘Maravilha das 4 Estações’, ‘Evely’, ‘Marcela’, 687 (‘Vera’ X ‘Sapore’), 784 (‘Vera’ X ‘Sapore’), was evaluated, using specific polyclonal antisera. The virus was not detected in seeds of ‘Verdinha’ genotype and seedlings of 687, ‘Marcela’ and ‘Evely’ after germination in a paper towel or in 687, 784 and ‘Marcela’ with themo1¹ resistance gene, after germination in a substrate. The individual evaluation of the number of infected seeds made by PTA-ELISA was 100% for ‘Vanessa Roxa’ and ‘Baba de Verão’, 87.7% for ‘Verdinha’, 46.6% for ‘Maravilha das 4 Estações’ and 16.6% for ‘Evely’. In the genotypes with the resistance gene the percentage was 15.6%, 26.6%, 90% in ‘Marcela’, 687 and 784, respectively. Virus detection in seeds and seedlings by PTA-ELISA was very efficient for both seeds and seedlings.