B小调是一个于B音开始的音乐的小调，组成的音有B、升C、D、E、升F、G、A及B（和声小调）。B小调是一个有2个升号的调。

它的相对大调是D大调，并行大调是B大调。

B minor is a minor scale consisting of the pitches B, C♯, D, E, F♯, G, and A. Its key signature consists of two sharps. The harmonic minor raises the note A to A♯. Changes needed for the melodic and harmonic versions of the scale are written with accidentals as necessary.