Herein, we report the synthesis, characterization, and field-effect properties of two cross-conjugated dithienylmethanone (DMO)-based alternating polymers, namely, PDMO-S and PDMO-Se. Both polymers possess high thermal stability, good solubility, and broad absorption spectra. Their electrochemical properties were investigated using cyclic voltammetry, indicating that PDMO-Se has higher HOMO/LUMO energy levels of -5.49/-3.49 eV than -5.57/-3.58 eV of PDMO-S. The two polymers exhibited promising charge transport properties with the highest hole mobility of 0.12 cm(2)V(-1)s(-1) for PDMO-S and 0.025 cm(2)V(-1)s(-1) for PDMO-Se. AFM and 2D-GIXRD analyses demonstrated that the PDMO-S formed lamellar, edge-on packing thin film with close - stacking. These findings suggest that cross-conjugated polymers might be potential semiconducting materials for low-cost and flexible organic electronics. (c) 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1012-1019