Supercontinuum generation in anomalous dispersion_flattened fibers through higher_order soliton compression effect is simulated and analyzed in detail. The results show that the second order differential constant of the dispersion parameter， dispersion parameter of the fiber and the pulse width, and peak power of the pump pulse are crucial to flat wideband supercontinuum generation, and the fiber length should also be dissimilarly chosen. It further shows that supercontinuum generation in the fiber mainly results from the interaction of self_phase modulation and group_velocity dispersions, and the higher_order nonlinear effects can be ignored.