It is necessary to investigate the characteristics and the evolution law of metal deformation by using the appropriate strain analysis method. The deformation of metal is complex, so there exists no useful method to amalyze the local deformation characteristics and to describe the global equivalent deformation of deformed metal. In this paper, we propose a statistical moment method of strain analysis. Statistical moment method builds up the relationship between micro quantities and macro strain. For instance, it is used to study the deformations of monocrystal under uniaxial load and the nanocrystalline under shear and shock, showing that moment method can not only describe and evaluate the local and the global deformation of metal but also distinguish elastic and plastic deformation by nonuniform coefficient. Moment method is a general and effective way to investigate the deformation mechanism of complex structure material.