D-flat minor is a theoretical key based on D♭, consisting of the pitches D♭, E♭, F♭, G♭, A♭, B, and C♭.

Its direct enharmonic equivalent, C-sharp minor, is normally used.

[1] However, unusually, two of Verdi's most well-known operas, La traviata and Rigoletto, both end in D-flat minor (although written with the five-flat key signature of the parallel major).

9, a solo bassoon interpolation following the main theme appears first in D-flat minor, returning twice more notated in C-sharp minor.

[2][3][4][5] However, D-flat minor is used on Max Reger's On the Theory of Modulation on pp.