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Clarification of rough nonalcoholic beer using microfiltration as an alternative to conventional filtration with filter aids presents scientific and technical challenges for the brewing industry. An experimental pilot plant was used to evaluate the permeability and selectivity of polymeric membranes in the clarification process. Cellulose acetate (CA) with pore sizes of 0.2, 0.45, 0.8, and 1.2 µm, together with cellulose nitrate (CN), nylon (NY), and polytetrafluoroethylene (PTFE) with a pore size of 0.45 µm, were used at transmembrane pressures (TMP) of 1.0 and 2.0 bar. The data corroborated that the flux values of the CA, CN, and NY membranes were almost the same and reduced drastically, whereas PTFE was not permeable at 1.0 bar and its flux at 2.0 bar increased at the beginning and decreased after reaching a maximum. At both TMP, the CN membrane displayed the highest rejection of suspended particles and haze-active proteins, while retention of polyphenols and color were highest for the NY membrane. The lower selectivity of the PTFE membrane can be attributed to its hydrophobicity and less interaction with the hydrophilic haze-active proteins. The results confirmed that by increasing the pore size of CA membranes the separation factor of the sensitive proteins and suspended particles decreased and permeability increased.