Sin has always been a part of human life and literature. The present paper tries to analyze the sins in Nathaniel Hawthorne work The Scarlet Letter: the sins of Hester, the Reverend Arthur Dimmesdale, and Roger Chillingworth. In the first place, the sin they commit and the way they each deal with it is explored. In the second place, the paper also further analyzes the effects of sin on the three characters. Through a close study of the characters in The Scarlet Letter, we draw closer to understand the theme of sin. Sin has always been a part of human life and literature. The present paper tries to analyze the sins in Nathaniel Hawthorne work The Scarlet Letter: the sins of Hester, the Reverend Arthur Dimmesdale, and Roger Chillingworth. In the first place, the sin they In the second place, the paper also further analyzes the effects of sin on the three characters. Through a close study of the characters in The Scarlet Letter, we draw closer to understand the theme of sin.