In this paper, an outphasing power amplifier(PA) with novel combiner is proposed. By replacing quarter wavelength impedance in classic structure with series microstrip lines with stop-band suppression, the proposed circuit achieved wide bandwidth while ensuring acceptable efficiency and linearity. Analytical and ADS simulation are presented in this work, an outphasing PA operating at center frequency 3.1GHz with 200MHz bandwidth is realized. The simulated results show excellent agreement in all cases considered.