The structure of the horizon and the Bañados-Silk-West mechanism in the rotating black hole surrounded by perfect fluid dark matter (PFDM) are investigated, there exist two extremal black holes with different intensity of PFDM for the fixed spin parameter. We study the range of allowed angular momentum, and center-of-mass (CM) energy near the horizon. It turns out that the CM energy of the collision at the horizon with the critical angular momentum can be infinite in the extremal black hole. For the non-extremal case, there is a finite upper b...
