In This study a thin film of nanometric TiO2 was sol-gel prepared and used for heterogeneous photocatalytic reaction to treat chlorobenzene in testing solution and to evaluate its removal efficiency. Conventionally, the material of photocatalyst was mainly fabricated in form of powder used in the suspension system. Although TiO2 powder has a high specific surface area for heterogeneous photocatalysis, it still leaves a great number of suspended solids in solution awaiting proper handling after the treatment is completed. Also, such suspended solids would pose ¡§shielding¡¨ effect from UV light, and thus affected the efficiency of photocatalytic degradation. To overcome this drawback, a proper mesh size of stainless steel webnet was first selected as a treatment substrate and TiO2 dip-coated, followed by calcination at 500¢J. The end product was used as the TiO2 photocatalytic film for this study. The film of TiO2, verified as anatase type of crystal lattice by XRD and SEM, contained particle sizes ranging from 10 to 20 nm. A solution containing chlorobenzene was used in the study to assess the extent of photocatalytic degradation by UV/TiO2 film. The test was to evaluate the effects of the number of dip-coating and calcining (thickness), initial pH, UV light intensity (@365 nm), and applied electric voltage on photocatalytic removal of chlorobenzene in the solution. The test results indicated that TiO2 film was capable of degrading chlorobenzene; however, enhancement of the degradation efficiency was found to be needed. It was also found that the degradation rate of chlorobezene increased with an increasing thickness of the film and UV light intensity. The pH of test solution was found to be insensitive to degradation of chlorobenzene, probably due to its non-dissociation nature. It was found that electric voltage exerted was unable to prevent electrons and holes from re-combining, and a negative effect of external voltage was even observed. Therefore, it was believed that voltage exertion was not beneficial to phtocatalysis in this study. Kinetics of the tests in this study assumed a pseudo-first-order reaction, which resulted in a rate constant k' = 1.3¡Ñ10-5¡]min-1¡^. The reaction rate was found to be proportional to the 0.7507 order of UV light intensity.