The limit strains of sheet metals under cold forming as well as hot press forming have been estimated with the aid of a new rigid -plastic meso-damage constitutive theory. A frame for the theory's practical application in limit strain analysis was presented and the in uences of microvoids and through thickness anisotropy on forming limits were systematically explored. Through comparison with existing experiment data, the validity of the present theory in damage evolution, deformation simulation and limit strain prediction was con rmed.MST/5673