diff --git a/CHANGELOG.md b/CHANGELOG.md
index fe3030e9..07da8abb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) a
 
 ## [Unreleased]
 
+### Changed
+
+- Correct the pattern for checking if a dynamic symbol can be converted into a label as a hash key.
+
 ## [2.4.1] - 2022-05-10
 
 - [#73](https://github.com/ruby-syntax-tree/syntax_tree/pull/73) - Fix nested hash patterns from accidentally adding a `then` to their output.
diff --git a/lib/syntax_tree/node.rb b/lib/syntax_tree/node.rb
index fdb40631..e8df1ea7 100644
--- a/lib/syntax_tree/node.rb
+++ b/lib/syntax_tree/node.rb
@@ -1388,7 +1388,7 @@ def format(q)
   module HashKeyFormatter
     # Formats the keys of a hash literal using labels.
     class Labels
-      LABEL = /^[@$_A-Za-z]([_A-Za-z0-9]*)?([!_=?A-Za-z0-9])?$/
+      LABEL = /\A[A-Za-z_](\w*[\w!?])?\z/
 
       def format_key(q, key)
         case key
diff --git a/test/fixtures/assoc.rb b/test/fixtures/assoc.rb
index cd3e5ed1..0fc60e6f 100644
--- a/test/fixtures/assoc.rb
+++ b/test/fixtures/assoc.rb
@@ -46,3 +46,5 @@
 { foo: "bar" }
 %
 { "foo #{bar}": "baz" }
+%
+{ "foo=": "baz" }