Uncial 0257 (in the Gregory-Aland numbering), is a Greek uncial manuscript of the New Testament. Paleographically it has been assigned to the 9th century.
The codex contains some parts of the Matthew 5-26; Mark 6-16, on 47 parchment leaves (29.5 cm by 22 cm). It is written in two columns per page, 23 lines per page, in uncial letters. It is a palimpsest, the upper text contains a lectionary 2094.
Currently it is dated by the Institute for New Testament Textual Research to the 9th century.
The Greek text of this codex is a representative of the Byzantine text-type. Aland placed it in Category V.
Currently the codex is housed at the Monastery of Agiou Nikanoros (2, ff. 1-16, 289-319) in Zavorda.