Recently, π-conjugated polymers have been studied vigorously for organic semiconductors Performance and air-stabiltiy are important factors for organic semiconductors. Fluorene has strong air-stability and anthracene derivertives have good performance as OTFTs. In this study, we had synthesized fluorene-nathracene based conjugated polymer for organic semiconductors. The polymer was synthesized by Suzuki coupling reaction and characterized by 1H-NMR, GPC. thermal analyses and UV-vis spectroscopy. Electrical conductivities and on/off ratios were Measured as well.