diff --git a/spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc b/spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc
index 75c5a71884..28cbe646a2 100644
--- a/spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc
+++ b/spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc
@@ -840,6 +840,9 @@ The following properties names can all be used:
 |`person.first-name`
 |Dashed notation, recommended for use in `.properties` and `.yml` files.
 
+|`person.first_name`
+|Underscore notation, alternative format for use in `.properties` and `.yml` files.
+
 |`PERSON_FIRST_NAME`
 |Upper case format. Recommended when using a system environment variables.
 |===