Uncial 091 in the Gregory-Aland numbering), õ 30 (Soden), is a Greek uncial manuscript of the New Testament, dated paleographically to the 6th-century.
The codex contains a small parts of the Gospel of John 6:13-14.22-24, on one parchment leaf (32 cm by 28 cm). The leaf survived in 3/4. The text is written in two columns per page, 23 lines per page, in large uncial letters. Letter iota is written with diaeresis.
The Greek text of this codex is a representative of the Alexandrian text-type with some alien readings. Aland placed it in Category II.
In John 6:23 the reading (the Lord had given thanks) is omitted, as in codices D, a, d, e, syr<sup>c</sup>, syr<sup>s</sup>, arm, geo<sup>1</sup>.
Currently it is dated by the INTF to the 6th-century.
The codex now is located at the Russian National Library (Gr. 279) in Saint Petersburg.