A method for determining geometric relationships of crystal reciprocal vectors on the two-dimensional planes obtained from an EBSD pattern includes steps of: geometrically correcting Kikuchi bands for obtaining the reciprocal vectors corresponding to the Kikuchi bands; selecting a set of reciprocal vectors which define a parallelogram with minimum area on the reciprocal plane as a two-dimensional basis for forming a grid, marking the basis; determining integer coordinates of other reciprocal vectors on the reciprocal plane relative to the basis, obtaining the deviations of the integer coordinates from the nearest grid nodes, marking the reciprocal vector with minimum deviation; fitting the length and the angel of the basis, redefining a new two-dimensional grid by the fitting result; repeating till all reciprocal vectors on the reciprocal plane are marked, wherein integer coordinates of the reciprocal vectors relative to the last two-dimensional basis now disclose the geometric relationships.