This paper analyzes the differences of the sound systems between Sichuan Dialect and English from the following two aspects: phonemes and sound combinations (We will discuss the other aspects of their sound systems in another paper). We are convinced that if language teachers have some knowledge of the transfer theory and if they know clearly the similarities and differences of mother tongue and English, it would be much easier for them to know the language focuses and difficulties for the learners and their teaching would be more effective.