Sulfur dioxide (SO₂) fumigation was studied in laboratory to determine its potential as an alternative treatment for postharvest control of stored product insects, confused flour beetle, Tribolium confusum Jacquelin du Val (Coleoptera:Tenebrionidae), and rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae).Three-hour fumigations with 0.1%–2.0% SO₂ were conducted against eggs, immature stages, and adults of the 2 insects at 20 °C. Effective control of both insects was achieved. However, there were considerable variations between the 2 insects and among different life stages. Confused flour beetle was more susceptible to SO₂ fumigation than rice weevil. Complete control of adults and all life stages of confused flour beetle was achieved in 3-h fumigations with 0.5% and 2.0% SO₂, respectively. For rice weevil, 3-h fumigation with 1.5% SO₂ resulted in 96.5% adult mortality and the fumigation with 2.0% SO₂ resulted in 99.27% mortality of adults and 87.5% mortality of immature stages.Three-hour fumigations with 1% SO₂ resulted in <5% egg survival to adults.The study demonstrated high efficacy of SO₂ fumigation against the insects and suggested that SO₂ fumigation has good potential for postharvest pest control on stored products.