This thesis is studying the “Le desir” which composed by German composer Theobald Boehm (1794-1881). The topic of the research is Schubert Trausalzer fantisia (Op. 9), it was developted and combined from variations and rondos. The whole song is sorrow but gorgeous.

Boehm was an important role in flute development history, not only a composer but also a flutist, improver and inventor. His greatest achievement was created and improved modern flute in 1847 which exceeded the limit of mechnical restrication. It led the flute float with the romantic period trand and also enhanced the music style and playing skills.

There are 3 chapters in this thesis. First chapter will be introducing the time background, Boehm's lifetime contribution and his music ideal.Second chapter is the analysis of compose and playing interpretation. Last chapter is conclusion, according to Boehm's life and time background, I expect to have more understanding to play the “Le desir” which fit the compose.