The Velocity-Metallicity Relation is the correlation between low Metallicity and high Velocity Dispersion within the local Milky Way. Low metallicity is associated with older stars, formed before supernovae and short-lived stars increased the metallicity of the Molecular Clouds, and stellar age has also been determined to be related (Age-Velocity-Metallicity Relation).

The velocity-metallicity relation is demonstrated by Peculiar Velocity Diagrams of stars of given metallicities and star types, that plot the Peculiar Velocity components based on the Galaxy of the given stars, the component radial to the galaxy and the component in the Galactic Plane circumscribing the galaxy, for the given stars, e.g., young A-Type Star.