Abstract：The spectral radius must be one of eigenvalues of the nonnegative matrix.However, it is very difficult to seek the eigenvalues of a matrix.Therefore, it is one of the core problems to estimate the spectral radius of nonnegative matrix in matrix theory.In this paper, by applying the famous Gerschgorin disc theorem and Brauer oval theorem, we proved two estimation for the upper bound of Hadamard product of two non-negative matrix of A and B.

Keyword：nonnegative matrix;Hadamard product;spectral radius;eigenvalue;