diff --git a/README.md b/README.md
index f7e03ca4cd8c..c78ae06765d3 100644
--- a/README.md
+++ b/README.md
@@ -194,7 +194,6 @@ value` mapping e.g.
 ```toml
 avoid-breaking-exported-api = false
 disallowed-names = ["toto", "tata", "titi"]
-cognitive-complexity-threshold = 30
 ```
 
 See the [list of configurable lints](https://rust-lang.github.io/rust-clippy/master/index.html#Configuration),
diff --git a/book/src/configuration.md b/book/src/configuration.md
index bbe1081ccad9..fac3e438c543 100644
--- a/book/src/configuration.md
+++ b/book/src/configuration.md
@@ -8,7 +8,6 @@ basic `variable = value` mapping eg.
 ```toml
 avoid-breaking-exported-api = false
 disallowed-names = ["toto", "tata", "titi"]
-cognitive-complexity-threshold = 30
 ```
 
 See the [list of configurable lints](https://rust-lang.github.io/rust-clippy/master/index.html#Configuration),