The functional approach to legal translation has had a great influence on the research of legal translation theory at home and abroad. The current academic research on functional approach to legal translation is fragmented, and there is few literature that systematically studies its development. This paper studies functional approach to legal translation from the perspective of academic history, which to some extent expands the research dimension of functional approach to legal translation. It is found that the functional approach to legal translation is not only influenced by German functionalism, but also learns and integrates the functional method of comparative law. Although this functional approach can largely solve the problems in legal translation practice, it has certain limitations in its own right.