The process of spin-orbit autoionization in HI has been studied using tunable coherent vacuum ultraviolet light, which had a spectral resolution of 0.01 Å. The high intensity of the coherent light source made it possible to record the spectrum under supersonic molecular beam conditions, where the HI had a rotational temperature of about 10 K. This spectrum of cold HI was very different from the high-resolution spectrum of 300 K HI recorded on the same apparatus, one difference being that it had very sharp resonances which were not present in the 300 K spectrum. These results are contrasted and compared with previous experimental work, and with a recent multichannel quantum defect calculation done by Lefebvre-Brion and co-workers. The similarities and differences between the autoionization in HI and the isoelectronic atom Xe are also discussed in light of these results.