The pulse radiolysis/kinetic absorption technique has been used to study the reactions of CH₂SH with O₂, NO, and NO₂. Rate constants of 8.5 × 10^-12, 1.9 × 10^-11, and 3.5 × 10^-11 cm³ molecule^-1 s^-1, respectively, were obtained at 1 atm and 298 K. Absorption spectra due to product species indicated that the reaction with O₂ proceeds via addition. There is evidence to suggest that addition is also the pathway for the NO and NO₂ reactions.