0M (zero M) or 0-M may refer to:
- 0m, an abbreviation for zero meridian, or Prime Meridian
- 0m, an abbreviation in measurement for zero metres
- 1E0m2, an abbreviation for square metre, an order of magnitude for expressing area
- 1E0m3, an abbreviation for cubic metre, an order of magnitude for expressing volume
- 0-m, an abbreviation for zero manifold
- Several terms related to 0 (number)
- Zero map, see constant function
- Zero morphism, a kind of morphism in category theory
- Zero matrix, a matrix with all entries being zero
- Agent Zero-M a range of secret agent toy weapons by Mattel Toys