Chez Scheme is a programming language, a dialect and implementation of the language Scheme which is a type of Lisp. It uses an incremental native-code compiler to produce native binary files for the x86 (IA-32, x86-64), PowerPC, and SPARC processor architectures. It has supported the R6RS standard since version 7.9.1. It is free and open-source software released under an Apache License, version 2.0. It was first released in 1985, by R. Kent Dybvig, originally licensed as proprietary software, and then released as open-source software on GitHub on 2016-05-13 with version 9.4.

Petite Chez Scheme is a sibling implementation which uses a threaded interpreter design instead of Chez Scheme's incremental native-code compiler. Programs written for Chez Scheme run unchanged in Petite Chez Scheme, as long as they do not depend on using the compiler (for example foreign function interface is only available in the compiler). Petite Chez Scheme was originally freely distributable and is now distributed open-source as part of Chez Scheme.