In unintentionally Si-doped AlN bulk samples, an electron paramagnetic resonance (EPR) spectrum with characteristics of a shallow donor, previously assigned to the shallow Si donor, was observed at room temperature in darkness. Temperature dependent studies of the EPR signal showed that Si is a DX center in AlN. However, with the negatively charged DX^– state determined to be only ∼78 meV below the neutral shallow donor state, Si should behave as a shallow dopant in AlN at normal device operating temperatures.