Serge Modular Music Systems is an analog modular synthesizer line originally developed by Serge Tcherepnin, with Rich Gold and Randy Cohen, at CalArts in late 1972. Production began in 1974, and the systems are considered one of the foundational designs of the "West Coast" approach to synthesis, alongside Buchla. Serge synthesizers use banana-jack patching rather than standard 1/4" or 3.5mm cables and are known for function-level patch points that expose internal circuit nodes, allowing modules to be combined in unusual ways beyond their nominal purpose.

The instruments are noted for modules like the Wave Multiplier, Dual Universal Slope Generator (DUSG), Triple Waveshaper, and the New Timbral Oscillator (NTO). Serge Tcherepnin later joined Random*Source as Chief Innovation Officer, and production of authorized Serge modules in 4U Paperface, Eurorack (3U), and panel formats is handled through Random*Source, based in Frankfurt, Germany. Modules such as the Medusa subharmonic oscillator and the Paperface 50th Anniversary system continue the design lineage.

The Serge format has a devoted following in experimental, ambient, and academic electronic music circles, and original 1970s–80s Serge panels remain sought-after vintage instruments.