As a masterpiece of Hawthorne’s works, The Scarlet Letter sets up on New England in the seventieth century and successfully depicts the cruelty of Puritan society and the kill to human nature. However, it seems that this is not the only purpose for the author to criticize the Puritanism. Hawthorne also endeavors to pursuit an ideal harmony through the image of the forest,which is omitted by most of the scholars who research Hawthorne’s works, especially for The Scarlet Letter. In this thesis, it aims to illustrate the ideal harmony from two perspectives: first, the image of the forest stands for the harmony of the primitive life; second, the image of the forest represents the harmony of the development both in body and mind.