A study on the role of sodium dodecyl sulfate (SDS) in hydrate nucleation under static conditions was carried out. The induction time of methane + propane hydrate nucleation at temperatures above the Krafft point was determined at various SDS concentrations. The induction time decreased as SDS concentrations increases and then levels off at 100 ppm at 285 K. The hydrate nucleation rate depended on SDS monomer concentration; it was less dependent on SDS micelle concentrations. The high nucleation rate in the presence of SDS was due to the hydrate-solution interfacial tension decreases after SDS adsorbs on the hydrate nuclei, reducing the energy barrier of hydrate nucleation. This is an abstract of a paper presented at the 2007 AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).