It consists of a single vellum leaf of a late second or early third century Greek codex, containing only a small part of the Acts of the Apostles.

[1] The history of Uncial 0189 is unknown prior to its current possession by the Staatliche Museen zu Berlin.

Uncial 0189 has evidence of the following nomina sacra: ΑΝΟΣ ΠΝΑ ΚΥ ΚΩ ΙΛΗΜ ΘΩ ΙΣΗΛ.

[5] Kurt Aland included Uncial 0189 in the Critical Apparatus of the 25th edition of Novum Testamentum Graece (1963).

[6] Uncial 0189 is classed as a "consistently cited witness of the first order" in the Novum Testamentum Graece (NA27).

"[8] A transcription of the text of Uncial 0189 was first published by Aarne H. Salonius in Zeitschrift für die neutestamentliche Wissenschaft in 1927.