The Musical and content harmony of Modern Iranian poetry is the core of this paper. There’ll be, initially, some arguments on the importance, coordination and the fitness existing between the poems’ components and the concinnity and elegance occurs, then the importance dedicated to such components by the poets and their beliefs to the harmonious coordination reflexes in their works will be scrutinized. The remarks of each poet, Nima, Shamloo, Akhavan and Shafiee Kadkani about the matter will be also discussed by some examples. It will finally be shown that their paying attention to such synchronism has a great role in the concinnity and influence of their poems. They have best used different kinds of music; external music (prosodic rhythm), internal music and side music (rhyme) to induct their concepts and to create such beauties.