2D semiconductor crystals offer the opportunity to further extend Moore's law to the atomic scale. For practical and low‐cost electronic applications, directly printing devices on substrates is advantageous compared to conventional microfabrication techniques that utilize expensive photolithography, etching, and vacuum‐metallization processes. However, the currently printed 2D transistors are plagued by unsatisfactory electrical performance, thick semiconductor layers, and low device density. Herein, a facile and scalable 2D semiconductor printing strategy is demonstrated utilizing the interface capture effect and hyperdispersed 2D nanosheet ink to fabricate high‐quality and atomic‐thick semiconductor thin‐film arrays without additional surfactants. Printed robust thin‐film transistors using 2D semiconductors (e.g., MoS2) and 2D conductive electrodes (e.g., graphene) exhibit high electrical performance, including a carrier mobility of up to 6.7 cm2 V−1 s−1 and an on/off ratio of 2 × 106 at 25 °C. As a proof of concept, 2D transistors are printed with a density of ≈47 000 devices per square centimeter. In addition, this method can be applied to many other 2D materials, such as NbSe2, Bi2Se3, and black phosphorus, for printing diverse high‐quality thin films. Thus, the strategy of printable 2D thin‐film transistors provides a scalable pathway for the facile manufacturing of high‐performance electronics at an affordable cost.