Electronic Journal of Differential Equations, Vol. 2001(2001), No. 30, pp. 1-9. Title: A blowup result in a multidimensional semilinear thermoelastic system Author: Salim A. Messaoudi (King Fahd Univ., Dhahran, Saudi Arabia) Abstract: In this work, we consider a multidimensional semilinear system of thermoelasticity and show that the energy of any weak solution blows up in finite time if the initial energy is negative. This work generalizes earlier results in [5] and [8]. Submitted February 20, 2001. Published May 7, 2001. Math Subject Classifications: 35K22, 58D25, 73B30. Key Words: Thermoelasticity; weak solutions; negative energy; blowup; finite time.