Terminology is closely related to the context. It is necessary for the extension of legal terminology translation principle from the intra-linguistic level to the extra context level. Starting from the perspective of transknowletology, this article, by induction method, conducts systematic description of the context relationship where legal terminology translation sets in. From the vertical perspective, it can be divided into macro, meso and micro level, corresponding to context of genealogy of law, context of local country, and context of text respectively. From the horizontal perspective, it can be viewed as inter-level context, namely, context of communication. When translating legal terminology, it has to be placed into complicated context structure relation with its inclusive knowledge also being considered in order to effectively achieve the aim of communication.