With the rapid development of information technology, using computers to assist English teaching has become an important method. The advanced network technology can optimize English teaching mode, improve English teaching quality, meet the personalized requirements of English learners and improve students’ English application ability. This article introduces the system structure of English network teaching. On the basis of this structure, the optimization principles and methods of English teaching under network environment are analyzed. The optimization principles mainly include the most optimization principle, the compatibility principle, the personalized teaching principle, the autonomous learning principle and the interactivity principle. The optimization methods include the optimization of teachers and students.