A multi-molecule model in biochemistry reaction is investigated in this paper.Firstly,the existence and stability of Hopf bifurcation for the ordinary differential system are obtained.Secondly,the partial differential system with diffusion is discussed and the diffusion-driven Hopf bifurcation is derived.Applying the normal form theory and the center manifold theorem,the direction and stability of this Hopf bifurcation are also given.Finally,some numerical simulations resorting to Matlab software are presen...