This article tries to explore and construct the assessment dimensions of language production competence in English. Constructing the dimensions is grounded on deep comparison and detailed analysis on the current influential syllabuses issued by China government and Europe and the national and international authoritative English tests as well. By the method of analyzing the key words in the syllabuses and tests’ criteria, this study has extracted the commonly acknowledged requirements and dimensions for assessing language production competence in English. In addition, from the perspective of psychology and cognitive linguistics, this article defines “language production competence in English” on the base of “language production competence”. Accordingly, the core components of language production competence and three central dimensions have been proposed with the emphasis of thinking’s role and importance in language production competence.