Forced surface segregation incorporated into non-solvent induced phase separation (NIPS) process for the preparation of the tri-block copolymer homoporous membrane was investigated by dissipative particle dynamics simulations. The copolymer bears hydrophobic cellulose acetate (CA), hydrophilic poly(poly(ethylene glycol) methyl ether methacrylate) (PEGMA) and low surface energy poly(hexafluorobutyl methacrylate) (PHFBM) segments. Simulation results show that the homoporous membrane can only be formed at the polymer concentration range of 15–40%. The analysis of the segment distribution of the membrane shows phase separation under different PHFBM/PEGMA block ratios. The introduction of PEGMA segments promoted the migration of low surface energy PHFBM segments to the surface of the membrane. By adjusting the mixing ratio of CA-PHFBM-PEGMA with CA from 0 to 60%, the controlled morphology regulation of the membrane can be realized. This work can serve as a guide and reference for the homoporous polymer membrane preparation via NIPS.