Ambipolar OFETs with balanced hole and electron field-effect mobilities both exceeding 1 cm2 V−1 s−1 are achieved based on a single-solution-processed conjugated polymer, DPPT-TT, upon careful optimization of the device architecture, charge injection, and polymer processing. Such high-performance OFETs are promising for applications in ambipolar devices and integrated circuits, as well as model systems for fundamental studies.