New fluorene derivatives with donor-acceptor-donor (D-A-D) structure were synthesized and characterized as solution-processable organic semiconductors for top-contact/bottom-gate organic thin-film transistors (OTFTs). Physicochemical properties of the new compounds were characterized by cyclic voltammetry (CV), UV-vis absorption spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), and density functional theory (DFT) calculation. All compounds were TFT active and compounds with strong electron withdrawing groups showed ambipolar semiconductor performance with electron mobility of up to 0.1 ㎠ V^-1 s^-1 and current on/off ratio of ＞ 10⁶.