An I2/K2S2O8 mediated multiple β‐C(sp3)−H functionalization reaction for the construction of polysubstituted furans has been established from readily available ethyl ketones and dimethyl sulfoxide. This transformation features dimethyl sulfoxide as a multipurpose precursor, acting as the precursor of the oxygen, methyl, and sulfur methyl units. Six new chemical bonds, involving two C−C, two C−O, and one C−S bonds were formed sequentially during the intermolecular oxidative annulation process.