Abstract: As an epochal figure in American legal history, Justice Holmes’ judicial opinions, legal ideas and related thoughts had a profound impact on the shaping and development of American legal thoughts. As a legendary figure with extraordinary life experience, the formation and development of his legal thoughts was also the product of a progressive process affected by many factors. In addition to the final maturation of his late legal thoughts, the formation of Holmes’ early legal thoughts can not be overlooked, which can be roughly divided into three stages: the learning and accumulation of legal knowledge, the preliminary summary of legal theories, and the gradual transformation of legal thoughts. In the process of the formation and transformation of his legal thoughts, they were nurtured and influenced by the common law tradition at the intellectual facet, and contained his insight and reflection on American legal realities at the judicial level. The stages and factors described above were of great significance to the transformation and final maturation of Justice Holmes’ legal thoughts.