Sn1-xFexO2 (x = 0.00, 0.01, 0.05, 0.10) nanoparticles were synthesized by a simple hydrothermal method. X-ray diffraction (XRD) reveals that all samples are pure rutile-type tetragonal phase and the grain size decreases with the increase of Fe content. High-resolution transmission electron microscopy (HRTEM) images show that the samples are spherical in shape and most grains are uniform in size with diameters of 5-6 mm. Magnetic measurements by using magnetic property measurement system (MPMS) show that the Fe-doped SnO2 nanoparticles exhibit paramagnetic behavior and the calculated values of the effective Bohr magnetron number are 4.94 mu(B)(LT) and 3.92 mu(B)(HT) for x = 0.01, 5.04 mu(B) for x = 0.05, and 4.81 mu(B) for x = 0.1, respectively. The decrease of magnetic moment per iron atom with the increase of iron concentration could be attributed to the antiferromagnetically coupled spins.