Abstract: The kinetics of oxidation of glycol and propanediol-1,2 by potassium diperiodatocuprate(Ⅲ) has been studied spectrophotometrically in alkaline medium at 25 ℃. The order with respect to Cu(Ⅲ) is found to be unity and that in α-diol to be about 1,7. The rate decreases with the increase of periodate concertration and increases with the increase of [OH~-]. The linear relationships between [a-diol]/κ′ and 1/[α-diol] and between 1/κ′ and [IO_4~-] are observed in our experiment, where κ′ is pesudo first-order rate constant. There is a negative ionic strength effect and under the protection of nitrogen gas, the reaction system can induce polymerization of acrylamide. The active species is assumed and a plausible mechanish involing free radical has been proposed. All the experimental phenomena can be explained by the rate equation derived from the mechanism. The second-order rate constants κ of rate-controlling steps fro glycol and propanediol-1, 2 are 0.42 and 1.60 mol~(-1)·L·s~(-1) respectively at 25 ℃.