Rh-doped barium titanate (BaTiO3) epitaxial thin films have been fabricated on SrTiO3 (100) substrates by pulsed laser deposition. The nonlinear optical properties of the films were determined using the z-scan method at a wavelength of 532nm with a laser duration of 10hs. The real and imaginary parts of the third-order nonlinear susceptibility x(3) were 5.71 × 10-7 esu and 9.59 x 10-8 esu, respectively. The real part value of x(3) of the Rh:BaTiO3 films is about one order larger than that of Ce-doped BaTiO3 thin films. The results show that Rh:BaTiO3 thin films have great potential applications for nonlinear optical devices.