Making use of the transformation relation among usual,
normal, and antinormal ordering for the multimode boson exponential quadratic
polynomial operators (BEQPO's), we present the analytic expression of
arbitrary matrix elements for BEQPO's. As a preliminary application, we
obtain the exact expressions of partition function about the boson quadratic
polynomial system, matrix elements in particle-number, coordinate, and
momentum representation, and P representation for the BEQPO's.