Wolfgang Amadeus Mozart was a famous Austrian composer and performer in the classical period, and also a ‘music prodigy’ of the Vienna classical music in the 18th century. Mozart's works are rich in different genres with natural content, reflecting his superb composition skills and the characteristics of his music. In addition to opera, piano sonatas are also an area that embodies Mozart's outstanding achievements and have extremely high artistic value. This paper analyzes Mozart's life, sonata development, composition stage and sonata style, etc., and studies the representative repertoire of the three stages of Mozart's creation of sonatas, hoping to provide some help to the researchers and performers of Mozart's piano sonatas.