This work, also known as Little Poems in Prose, composed of fifty poems created between 1855 and 1864, is the product of a long and tortuous elaboration. Its author attributes to it the importance of a masterpiece that completes and broadens the perspectives of The Flowers of Evil, however it was not constituted as a finished work until the posthumous edition of his complete works (1869). More than a work conceived as such, The Spleen of Paris is the conjunction of an entire innovative literary line, the product of a writer who seeks a form of expression that responds to some of his fundamental concerns. This poetic collection transcends each of his works separately, it is considered as the book of Humanity of Charles Baudelaire, it captures a tormented city: the urban man victim of daily misery, the society of the foreigner, the frightening agitation of the city, etc., all this as a response to a proclamation of the suffering man as the center of art. The Spleen of Paris marks an absolute beginning in contemporary literature –with The Flowers of Evil, Baudelaire brought romantic poetry to its culmination, which in turn was a tributary of classical poetry–, it means a new poetic opening, this time with the tools of poetic prose, seeking that this poetry be born from a combination of images and sensations that assume the musical functions of prosody and rhythm in the poem in verse. The author fully fulfills his objective, achieving poems with great emotional content, surrounded by a magical spell and a depth in perspective that amazes the reader.