Carl Maria von Weber（1986 -1826）, a significant figure of early Romantic composers in the late-eighteenth and early-nineteenth centuries, had composed nine operas, and his most influential work is opera Der Freischütz. In the history of music, the creation of Der Freischütz is considered as a symbol, the birth of German nationalism and German Romantic operas. This thesis discusses the interpretation in performing Fantaisie sur le Freishütz for Flute and Piano by Paul Taffanel（1844-1908）through analyzing the composing motives, going over the biographies of Weber and Taffanel, and looking into relations between the music and story along with comparison between score examples of opera Der Freischütz for piano solo and Fantaisie sur le Freishütz for Flute and Piano. Written in five parts, the motives and purposes for research mentioned above are included in Chapter 1 whereas Chapter 2 briefly describes the biography of Weber, Chapter 3 introduces Taffanel’s musical background and his important contributions to the developing history of the flute, Chapter 4, centered on Der Freischütz, firstly introduces opera Der Freischütz , followed by Fantaisie sur le Freishutz for Flute and Piano, and ends with story-telling demonstration along with the score examples of the two pieces, and Chapter 5 attests the analysis of composition and interpretation of preforming Fantaisie sur le Freishütz for Flute and Piano, through the aspects of harmony, tonality, style, and story background, to conclude the findings. Along discoveries through researching and practicing, the research is based on form and harmony analysis, relevant books, references of documents, opera Der Freishütz for piano solo, programs of concerts, musical CDs, music encyclopedias, dictionaries, and other sources.