This study advances our knowledge regarding the character of the version of Daniel attributed to Theodotion within the larger framework of the Theodotionic problem in Septuagint research. This is achieved in two ways. In addition to demonstrating the recensional character of Theodotion-Daniel and describing its revising techniques, it also breaks new ground on Theodotion’s Hebrew-Aramaic source. The findings compellingly argue for the theory that Theodotion-Daniel is a systematic revision of the Old Greek in conformity with a Semitic text form which often preserved original readings against the Masoretic Text and the Qumran scrolls.