A diblock copolymer is a linear-chain molecule consisting of two types of monomer.Mathematical models for diblock copolymers can aid researchers in studying the material properties of products as upholstery foam, adhesive tape and asphalt additive. Such models incorporate a variety of factors, including concentration difference, connectivity of the subchains, and chemical potential. We consider a flow of two macroscopically immiscible, viscous compressible diblock copolymer fluids. We first give the derivation of this model on the basis of a local dissipation inequality. Second, we prove that there exist weak solutions to this model. The proof of existence relies on constructing an approximating system by means of time-discretization and vanishing dissipation. We then prove that the solutions to these approximating schemes converge to a solution to the original problem. We also cast thought on the large-time behavior with regularity assumption on the limit.