Unna I is an electoral constituency (German: Wahlkreis) represented in the Bundestag. It elects one member via first-past-the-post voting. Under the current constituency numbering system, it is designated as constituency 144. It is located in the Ruhr region of North Rhine-Westphalia, comprising the southern part of the district of Unna. Unna I was created for the 1965 federal election. Since 2009, it has been represented by Oliver Kaczmarek of the Social Democratic Party (SPD).