The Aramaic fragments of the Toldot Yeshu have long been recognized as the oldest version of this polemical tradition which was translated, and elaborated, into many other languages, and transmitted throughout the centuries after its inception. The Aramaic dialect of these fragments has been described as an artificial mixture of Palestinian and Babylonian Aramaic. A grammatical analysis of each of these fragments reveals that they display the signs of an incomplete dialectal translation from Western to Eastern Aramaic, with conspicuous Western Aramaic morphemes in one fragment. On the other hand, the vast majority of the text of the other fragments is written in a blend of two Eastern Aramaic stocks, one literary type Aramaic which resembles that of Onqelos, and one more colloquial dialect which comes very close to Talmudic Aramaic. Finally, the hybrid construction of the agreement pronoun attached to the nota objecti, followed by the direct object marked by, suggests that the text received further linguistic updating in the West at a relatively late stage in the textual history of this tradition.