  We study collision of two domain walls in 5-dimensional asymptotically Anti
de Sitter spacetime. This may provide the reheating mechanism of an ekpyrotic
(or cyclic) brane universe, in which two BPS branes collide and evolve into a
hot big bang universe. We evaluate a change of scalar field making the domain
wall and can investigate the effect of a negative cosmological term in the bulk
to the collision process and the evolution of our universe.
