Recently, the invention of a triboelectric nanogenerator (TENG) has provided an effective approach to convert ambient mechanical energy into electricity. The working principle of the TENG is based on the coupling of contact electrification and electrostatic induction. Contact-induced charge transfer between two materials with opposite tribopolarity results in a potential difference when they are separated. This potential difference is an inner electrical signal created by the external mechanical force, which could be used as a gate signal to tune/control the carrier transport characteristics in FET as the same effect as applying a gate voltage. Utilizing the coupled metal oxide semiconductor field-effect transistor and triboelectric nanogenerator, we demonstrate an external force triggered/controlled contact electrification field-effect transistor (CE-FET), in which an electrostatic potential across the gate and source is created by a vertical contact electrification between the gate material and a ï¿½foreignï¿½ object, and the carrier transport between drain and source can be tuned/controlled by the contact-induced electrostatic potential instead of the traditional gate voltage. With the two contacted frictional layers vertically separated by 80 ?m, the drain current is decreased from 13.4 to 1.9 ?A in depletion mode and increased from 2.4 to 12.1 ?A in enhancement mode at a drain voltage of 5 V. Compared with the piezotronic devices that are controlled by the strain-induced piezoelectric polarization charged at an interface/junction, the CE-FET has greatly expanded the sensing range and choices of materials in conjunction with semiconductors. The CE-FET is likely to have important applications in sensors, human silicon technology interfacing, MEMS, nanorobotics, and active flexible electronics. The CE-FET is based on the MOSFET and contact electrification effect, which can be used as fundamental components in novel triboelectronic devices and systems. We call this tribotronics, a new field of research and applications in flexible electronics. Tribotronics is about the devices fabricated using the electrostatic potential created by triboelectrification as a ï¿½gateï¿½ voltage to tune/control charge carrier transport in the semiconductor. Tribotronics is a field by coupling the semiconductor with triboelectricity, which is an extension of piezotronics first proposed in 2007, and also a profound application of TENG first proposed in 2012. By the three-way coupling among triboelectricity, semiconductor, and photoexcitation, plenty of potentially important research fields are expected to be explored in the near future.