Henry David Thoreau was wholeheartedly in love with nature and he devoted almost all his life time to observation,appreciation and study of nature.Thus he formed a deep understanding of nature.In 1845,Thoreau began a two-year and twomonth residence at Walden Pond.His life was lonely but full of fragrance.He wanted to live meaningfully,confront the essential facts of life and live a simple life.Based on the review of the literature related to this topic,this paper aims to study Henry David Thoreau’s spiritual world,especially reflected in his famous book—Walden.