Every language is assumed to be structurally and culturally unique. The relationship between language and thought has long been discussed by scholars since Plato’s time and various hypotheses have been made concerning it. The Sapir-Whorf hypothesis including Linguistic Determinism and Linguistic Relativity, the most provocative one， suggests that the way we perceive and categorize reality is completely or partly determined by the language we speak. This paper aims at leading learners to have a better understanding of the relationship between language and thought and further gain a better experience of second language acquisition by conducting a critical review on this hypothesis from several aspects as following. Toward this end, a general introduction to the Sapir-Whorf Hypothesis will be given by the author, furthermore the disadvantages and advantages of the hypothesis will be discussed. Finally also attention will be paid to the arguments challenging its validity. Hopefully, it is expected to shed light on foreign language teaching and learning in China.