Different from philosophies that guide foreign language skills training and foreign language teaching, the philosophy of Content and Language Integration (CLI) has great potentials in improving learners’ foreign language proficiency and developing learners’ content-area knowledge, abilities and competencies simultaneously, and it has unique strengths in guiding the development of foreign language teaching (FLT) materials. This article analyzs different philosophies that guided the development of FLT materials, summarizes the experience of CLI-guided material development, and presents five principles that may guide the development of content and language integrated FLT materials. It is hoped that the experience and the principles can shed some light on the development of FLT materials and the improvement of foreign language education.