Abstarct: In this research, we have studied Brownian motion of a heavy particle in thermalized plasma. This plasma is made of quarks and gluons and it is different than normal plasma. Since, coupling constant is stronge, usual perturbation method dose not work for studing of this plasma. For this purpose; the AdS/CFT duality is used. baxsed on the AdS/CFT duality to explain temperature we have to consider a black hole in the bulk. Also; the particle is described by end of classical string that starts fram boundary of AdS5 space and extends to the black hole. Brownian motion of the particle leads to perturbation in the string and coefficients of the Langevin equation can be obtained precisely from study of behavior string under this perturbation. With this method longitudinal and transveres langevin coefficients calculated; precisely.