Ethnic preparatory English course is characterized by short learning time and little examination pressure but it plays an important transitional role in the future college English learning. The fact that some ethnic preparatory students play mobile phones in English classes could seriously affects their learning efficiency. However, rational use of mobile phones in English classes will bring positive impacts on students such as improving their learning efficiency and broadening their knowledge. Students' weak awareness of independent learning diminishes these positive impacts. Therefore, teachers can actively guide and train students to use mobile phones for English learning. In addition, they can develop students' awareness and ability of independent learning. Teaching practice has shown that mobile phones and the Internet can help improve English classroom teaching and the English learning ability of ethnic preparatory students.