Using hydroxypropyl-beta-cyclodextrins (OH-beta-CD) as aqueous phase additive, nanocavity-contained thin film composite (TFC) nanofiltration (NF) membranes were prepared by interfacial polymerization of piperazine (PIP) and trimesoyl chloride (TMC). Attenuated total reflectance Fourier transform infrared and X-ray photoelectron spectroscopy analysis confirmed the successful incorporation of OH-beta-CDs into the thin polyamide rejection layers. The rejection layer morphologies and structures, surface properties and separation performances of the prepared TFC membranes were greatly influenced by the OH-beta-CD mass ratio in aqueous phase during interfacial polymerization. With appropriate OH-beta-CD mass ratios (20-60%), the prepared TFC membranes showed enhanced water flux, reduced R-NaCl, increased R-Na2SO4 and R-MgSO4, which led to highly improved divalent to monovalent ions selectivity. These nanocavity-contained TFC membranes exhibited the potential to apply in desalination pretreatment.