This paper will examine the manuscript evidence for Philo’s treatise De Decalogo. Particular attention will be given to the oldest manuscript, Vaticanus gr. 316, which was investigated by Cohn only after the publication of the critical edition of De Decalogo. Although Cohn devoted an article to this ms., he seems to have concentrated on its text of the works in Cohn-Wendland vol. 5, for which he could still cite the ms., rather than on its text of the already edited works. Thus, a more detailed look at that ms. is warranted. Another area of emphasis will be the evidence supplied by various collections of extracts and by citations in the catena on Luke by Nicetas. This secondary evidence often provides valuable readings.