There are some pragmatic failures in the E-C translation of science and technology. The pragmatic failures in the translation of EST consist of two categories: language pragmatic failures and social pragmatic failures. Language pragmatic failures are mainly due to 1) the word mistranslation of literal meaning; 2) mistranslation caused by violation of Chinese word collocation and sentence patterns; 3) misuse of borrowing the structure and expression in English text. While social pragmatic failures are mainly caused by the gap between the Sino?British culture and value differences. Some techniques, such as transliteration, transference, amplification, omission, note etc. can be applied in the translation in EST to reduce pragmatic failures.