This paper is to analyze In America from the perspective of New Historicism, with its body part comprising three aspects, namely multiple themes, feminist features of characterization and narrative features. Sontag’s sense of social criticism, her Utopian ideal can be detected through the detailed analysis of its multiple themes; her feminism comes into sight with the discussion of the female as well as male characters in this book.What’s more, changeable and uncertain historical narratives provide more possibilities to interpret this work. Conclusion is drawn that Sontag with her fresh view and discourse reinterprets history demonstrating the spirit of New Historicism.