A bio-chip adapted for separating and concentrating particles in a solution includes a chip body defining a receiving space therein for receiving the solution, an inner electrode disposed in the receiving space, an outer electrode unit disposed in the receiving space of the chip body and including a first outer electrode that is spaced apart from and surrounds the inner electrode, and a second outer electrode that is spaced apart from and surrounds the first outer electrode, and a power source electrically connected to the inner electrode, the first outer electrode, and the second outer electrode. A method for using the bio-chip to separating and concentrating the particles in the solution is also disclosed in the present invention.