The author constructs a parallel corpus consisting of 100 pieces of contemporary English-Chinese translation prose，and a comparable corpus composed of 100 pieces of contemporary original Chinese prose．By analyzing these two corpora on the vocabulary，sentence and discourse level，with reference to LCMC which acts as a balanced corpus for the 100 translated Chinese prose，the researcher tries to explore the norms governing the contemporary English-Chinese prose translation．With the help of Wordsmith and other analytical tools，the research finds out the linguistic features of these corpora，from which we conclude that in the usage of specific words，the operational norms the translators adopt indicate a trend toward conventional expectation norm，while in the structure of sentences，paragraphs and textual arrangement，they indicate a trend towards foreignness expectation norm．Besides，the research also finds that translation is indeed a“third code”，which has its distinctive features．What's more，the paper finds out the basic unit of translation is sentence．