本研究旨在探討鋼琴奏鳴曲的演變發展及風格特徵。透過音樂歷史中巴洛克時 期、古典時期、浪漫時期與二十世紀四個時期的演變過程探討出背景、曲式與風格的差異， 並作比較。 　　初超的鍵盤奏鳴曲形式很自由，情感亦單純。古典時期則固定一種標準格式，並強調情 感及理知、形式及內容的均衡與對稱，也是鋼琴奏鳴曲的巔峰時期。浪漫時期因不喜稅格式 的限制而呈現不熱衷的趨向，奏鳴曲常隨著情感自由擴充或變化個人的理想中的樂曲模式。 二十世紀時期則處處呈現不安定，不規則與不對稱。因著熱衷程度的遽減使鋼琴鳴曲自二十 世紀中以後逐漸被帶進衷退與近乎終結。 　　鋼琴奏鳴曲隨著歷史不斷在演變。每個世紀，每時期都有不同的亡式與風格。然而值得 一提的是「綱琴奏鳴曲」這個名詞、曲類卻歷久不衰，未曾改變過。

　　　　　The purpose of this study is to approach the evolution and characteristics of piano sonatas. Through musical history of four periods: Baroque, Classicism, Romanticism and Modern, the differentiation and comparison of backgrounds, forms and characteristics are researched. At first, the keyboard sonatas from emphasizing the regularity and equality of affection、intellectuality、form and material. The period then became the peak of piano sonatas. In the Romantic era, the enthusiasm of composing piano sonatas declined due to the formal restriction. Piano sonatas were mostly free in forms either with expansion or variety for personal idealism. Unstability, irregularity and unequality were evoked at the twentieth century. After the mid-20th century, the enthusiasm for writhing piano sonatas was suddenly lost, which almost brought the piano sonatas into an end of further development. Piano sonatas keep changing through the whole western music history. There are different forms and characteristics of piano sonatas in each century. However, a worth mention is that "piano sonata" itself owns a long last meaning which has never and ever been changed.