In this paper, the theme of this thesis is Piano Sonata No. 26 in E-flat Major "Das Lebewohl”, Op. 81a, by German composer Ludwig van Beethoven, 1770-1827, music exploration, is divided into five chapters.

The first chapter describes the origin of the research topic, the scope and information of the study. The second chapter describes Beethoven's musical career and creation, which is divided into three periods (1795-1800), medium (1801-1814), and evening (1815-1827). The third chapter explores the piano sonata in Beethoven's mid-term, first explains the outline of the work, and then explains the creative background and characteristics. The first chapter analyzes and interprets the first movement, “Das Lebewohl”, the second movement, the “Abwesenheit” and the “Das Wiedersehen”, and explores the musical structure with the vision of the researcher. Playing experience and interpretation of the content and the appropriate way to play.