The quantum Hall body is a kind of topological insulating state with insulated inside and conductive edge. It has a unidirectional conductive edge state with zero resistance. The topological structure of the system promise the existence of edge states, which are the essential result of coupling of magnetic moment and momentum of electrons. In the strong magnetic field, electrons can only take the magnetic moment in one direction, so the electron in edge state canonly move in one direction, and cannot be scattered back. Starting form Hamiltonian of one-dimensional directional moving of lattice system, we discussed the low energy excitation and barrier scattering of edge state electrons in quantum Hall system, andits energy eigenstates and eigenvalues were obtained. The results show that: the energy spectrum of the edge state electron is linear, and its quantum tunneling probability is 1, which is independent of the barrier height. It will not be scattered, and its resistance is zero.