Covalent organic frameworks (COFs) with crystalline imide structure achieved remarkable application in the field of water treatment membrane. In this work, 1,3,5-triformylphloroglucinol (Tp) and benzidine (Bd) or melamine (Me) monomers as the assemble units were firstly in-situ interfacial polymerized upon polysulfone (PSf) porous substrate to form COFs composite membrane with a thin and stable COFs selective layer. Furthermore, adding melamine monomer during interfacial polymerization between Tp and Bd monomers could further introduce a triazine ring type-keto-enol tautomeric type into COFs selective layer, and adjust the molecular network structure and crystallinity of the COFs layer with variable pore aperture. The results indicated that the as-prepared TpBd/PSf and TpBdMe/PSf membranes could be efficiently applied for dye separation process with congo red rejection above 99.0%. Compared with TpBd/PSf membrane, water permeability of TpBdMe/PSf membrane increased from 33.6 L·m−2·h−1·bar−1 to 62.2 L·m−2·h−1·bar−1. Moreover, both TpBd/PSf and TpBdMe/PSf membranes exhibited excellent anti-fouling property, chemical and thermal stability. This work develops a facile method to prepare the imine-linked COFs membrane with variable pore aperture by changing reaction parameters and selecting appropriate amine monomers.