1. A speech-to-text system comprising: a speech recognition unit which performs speech recognition of speech data and outputs recognition result information as a sub-word string including time information of the speech data; a text editor unit which creates edit result text which is text information written-out from the speech data; a sub-word conversion unit which converts the edit result text into a sub-word string; and a matching unit which collates the edit result text with the recognition result information according to consistency of sub-words to thereby match the edit result text and the speech data.