In this paper, an expanded topology for dual-band Wilkinson power divider (WPD) with improved flexibility is presented. The addition of the expansion factor m enables dual-band power dividers with higher frequency ratios to be realized. The PD with the same frequency ratio can be realized by using different m-parameter, which means different design parameters and performance. General design formulas are educed from the even- and odd-mode analysis. Since there is no lumped capacitance and inductance, this topology can be used for high-frequency applications. Two design cases are fabricated and measured, the measured results are in good agreement with the simulated results.