The reaction of [V(PS3")] (1) (PS3"=[P(C H -3-Me Si-2-S) ] ) with H O led to the formation of [V (PS3")(PS2"S )] (2) (PS2"S =[P(C H -3-Me Si-2-S) (C H -3-Me Si-2-SH)] ), indicating a hydrogen atom transfer from H O to a bound thiolate in 1. Furthermore, the reaction of 1 with CH OH gave the generation of complexes 2 and 3, [V (PS3")(PS2"S )] (PS2"S =[P(C H -3-Me Si-2-S) (C H -3-Me Si-2-SCH )] ), implying that C-O and O-H bonds are cleaved by 1. Quantum mechanical calculations were performed to provide the mechanistic understanding for the reactivity of 1 with water. A key transition state with a lower kinetic barrier is identified. It involves an O-H bond cleavage by a dissociated thiyl radical with an interaction between an OH group and a neighboring bound sulfur donor. To our knowledge, the reactivity of 1 represents a new mode for water activation conducted through cooperation between a metal-stabilized thiyl radical and a neighboring thiolato donor.