Abstract: This paper mainly deals with the properly posed set of functionals for bivariate Birkhoff interpolation.By means of the theory and method of constructing the properly posed set of functionals for bivariate osculatory interpolation,the paper gives a new constructive method of properly posed sets of functionals in bivariate Birkhoff interpolation:plane algebraic curve superpositon process.Which is realized by superimposition.

Key words: bivariate Birkhoff interpolation, properly posed sets of functionals, plane algebraic curve