In this study, we present a fully complementary metal–oxide–semiconductor-compatible ternary inverter with a memory function using silicon feedback field-effect transistors (FBFETs). FBFETs operate with a positive feedback loop by carrier accumulation in their channels, which allows to achieve excellent memory characteristics with extremely low subthreshold swings. This hybrid operation of the switching and memory functions enables FBFETs to implement memory operation in a conventional CMOS logic scheme. The inverter comprising p- and n-channel FBFETs in series can be in ternary logic states and retain these states during the hold operation owing to the switching and memory functions of FBFETs. It exhibits a high voltage gain of approximately 73 V/V, logic holding time of 150 s, and reliable endurance of approximately 105. This ternary inverter with memory function demonstrates possibilities for a new computing paradigm in multivalued logic applications.