Victorian sensation novels, in addition to their scandalous topics such as fraud, murder, adultery, bigamy, and madness, refer to Victorian laws and their construction by social and cultural standards. As a significant sensation novelist, one of the most important subjects Wilkie Collins calls for attention is illegitimacy, a social, political, and literary topic he recurrently employs in his fiction. In his novels The Woman in White (1860) and No Name (1862), he dwells on this issue, motivating the characters’ crimes and scandalous acts. In both novels, illegitimate characters act illegally to reconstruct their identities by challenging Victorian norms especially about illegitimacy. Concerning his life and his critique of Victorian laws and moral certitudes, this paper explores how Wilkie Collins employs and questions the theme of illegitimacy about crime, sensations, and social and legal problems that influence illegitimate children. After briefly examining illegitimacy and laws about it in Victorian England, it explores how the concept of illegitimacy is shaped and influenced by Victorian conventions and gender ideologies in the two novels.