ZnO–bentonite nanocomposite assisted photocatalytic degradation of phenol under UV-irradiation in Continuous Stirred Tank Reactor (CSTR) revealed that phenol can be continuously removed from aqueous stream using a very simple set-up with good efficiency. The batch experiments suggested that removal of phenol follows 1st order reaction kinetics with Langmuir type of adsorption characteristics. It is observed that degradation of phenol is more pronounced under basic conditions rather than acidic ones mainly due to generation of phenoxide ion at pH 12. On the other hand, better results are obtained at lower flow rates owing to proper adsorption and subsequent degradation process. 2,4,6-Tripnenoxy phenol and adipic acid are formed during the photo-oxidation of phenol due to generation of hydroxyl radicals (OH•).