We report the atomic N-doped SnO2 films with p-type conduction grown via reactive sputtering at high nitrogen partial pressure. From the high-resolution x-ray photoelectron spectroscopy (XPS) and x-ray diffraction patterns, it is deduced that the N 1s with binding energy of 397 eV could be attributed to the atomic N in the SnO2 films. In addition, the results of Hall effect measurement indicate that the atomic N incorporated substitutionally at O sites act as acceptors, which is responsible for the p-type conduction of the N-doped SnO2 films. It is believed that these findings should stimulate further research on p-type SnO2 films and SnO2-based ultraviolet optoelectronic devices.