CCAST, World Lab, Beijing 100080, Peoples R China
; Inst High Energy Phys, Beijing 100039, Peoples R China
We investigate CP violation asymmetry in the decay of a tau slepton into a tau neutrino and a chargino in the minimal supersymmetric standard model. The new source of CP violation is the complex mixing in the tau slepton sector. The rate asymmetry between the decays of the tau slepton and its CP conjugate process can be of the order of 10(-3) in some region of the parameter space of the minimal supergravity scenario, which will possibly be detectable in near-future collider experiments.