Abstract: Provided is a speech translation system for receiving an input of the original speech in a first language, translating an input content into a second language, and outputting a result of the translating as a speech, including: an input processing part for receiving the input of the original speech, and generating, from the original speech, an original language text and the prosodic information of the original speech; a translation part for generating a translated sentence by translating the first language into the second language; prosodic feature transform information including associated prosodic information between the first language and the second language; a prosodic feature transform part for transforming the prosodic information of the original speech into prosodic information of the speech to be output; and a speech synthesis part for outputting the translated sentence as a speech synthesized based on the prosodic information of the speech to be output.