Não.
Não há absolutamente nada nos filmes da Trilogia Original (nem em suas novelizações) para indicar que Han soube da identidade de Vader.
Luke se refere a Vader como seu pai em sua cobertura com Leia , mas não há nada que mostre que Han foi posteriormente informado deste segredo, pelo menos antes do final do filme.
“Oh, no. No.” She laughed, “it’s not like that at all—Luke is my brother.” Han was successively stunned, embarrassed, and elated. This made everything fine, just fine.
He took her in his arms, embraced her, lowered her back down into the ferns … and being extra careful of her wounded arm, lay down there beside her, under the waning glow of the burning Star.
Eu imaginaria se ela já tivesse dito a ele que Vader era o pai de Luke , o processo de pensamento dele teria sido mais ...
Tudo isso dito, Han evidentemente descobriu algum tempo nos 20 anos intermediários entre o retorno de Jedi e o Despertar da Força;“Oh, no. No.” She laughed, “it’s not like that at all—Luke is my brother.” "Bloody hell," thought Han. "But surely that means that Darth Vader was her father too!"
What could he say to that? What possible response could he give to a willful denial of reason? “He’s gone, Leia. He was always drawn to the dark side. There was nothing we could’ve done to stop it, no matter how hard we tried.” His final words were the hardest to get out. “There was too much Vader in him.”