Idiom is fixed phrases or sentences and extracted from the language which have been used for a long time. It includes proverbs, slangs, dialects, etc. It usually shares the characters of a tight, strict structure, simple form, brilliant meaning, understandable image, vivid expression and so on. As the essence and treasure of ethnic language idiom shows the life, social custom, religious belief, value, history and culture of a nation as well as the way of thinking with strong ethnic and cultural characteristics.This paper has a tentative illustration on English idioms from the viewpoint of definition, characteristics and strategies of translation.