This article aims to analyze the important aspects of the philosophical point of view of the esoteric doctrine opening up to the philosophy of Pythagoras on one side, mathematics on the one hand, mysticism and cosmogony on the one hand, and cosmology on the other, and to follow their traces in science of music through names that can be considered the successors of the Pythagorasteaching.For this purpose, first a general information about Pythagoras philosophy and school will be given, then the mathematical basics of Pythagoras' theory of music will be mentioned. While explaining how the Pythagoras philosophy established the relationship between music and mathematics, the sound experiments of Pythagoras on a device called "monochord" will be mentionedand his discoveries as a result of these experiments will be explained. At the beginning of these discoveries, without a doubt, two important musical discoveries called "Pythagorean scale" and "Pythagorean coma" comes. Pythagoras' sound intervals and harmonic octaves determined based on numerical ratios, its relation to acoustic sound proximity, its relationship with pentatonic, diatonic and chromatic sound sequences and his views on tetrad-tetraktis numbers will bediscussed andafterrevealingtherelationshipbetweenmusicand mathematics in Pythagoras philosophy, the effect of Pythagoras philosophy on Kepler's Harmonices Mundiwill be discussed. Pythagoras's influence on Kepler reached out to musicians such as Hindemith, Ligeti, Holzt, Blanchet and Stockhausen through Kepler's idea of "the music of the celestial globe", causing them to write compositions inspired by the sounds of planets or stars. Thus, the Pythagorean philosophy created a new perception of "cosmicmusic"throughKepler.Ontheotherhand,wecanfind Pythagorean tones in the music compositions of musicians such as Bach, Rebel, Monteverdi, Schönberg, Webern and Herschel. Therefore, while explaining the relationship between music and mathematics in Pythagoras philosophy, the effect of Pythagorean philosophy on both science of music and cosmology will be discussed in this article.