Locrian may refer to:
- Locrians, an ancient Greek ethnic group
- Locrian Greek, ancient Greek dialect spoken by the Locrians
- Locris, the territory of the Locrians
In music:
- Locrian mode, a musical mode or diatonic scale
- Major Locrian scale, the scale obtained by sharpening the second and third degrees of the locrian mode
- Locrian sharp 2 or Half diminished scale, a musical scale commonly used in jazz and some rock
- Locrian (band), Chicago-based experimental music duo