diff --git a/changelog/fix_numeric_node_sign_to_return_boolean.md b/changelog/fix_numeric_node_sign_to_return_boolean.md
new file mode 100644
index 000000000..7f6ee39b2
--- /dev/null
+++ b/changelog/fix_numeric_node_sign_to_return_boolean.md
@@ -0,0 +1 @@
+* [#380](https://github.com/rubocop/rubocop-ast/pull/380): Fix `RuboCop::AST::NumericNode#sign?` to return boolean. ([@viralpraxis][])
diff --git a/lib/rubocop/ast/node/mixin/numeric_node.rb b/lib/rubocop/ast/node/mixin/numeric_node.rb
index 69e7ab146..66e0dd51a 100644
--- a/lib/rubocop/ast/node/mixin/numeric_node.rb
+++ b/lib/rubocop/ast/node/mixin/numeric_node.rb
@@ -15,7 +15,7 @@ module NumericNode
       #
       # @return [Boolean] whether this literal has a sign.
       def sign?
-        source.match(SIGN_REGEX)
+        source.match?(SIGN_REGEX)
       end
     end
   end
diff --git a/spec/rubocop/ast/float_node_spec.rb b/spec/rubocop/ast/float_node_spec.rb
index 8f2803313..b4fe5491f 100644
--- a/spec/rubocop/ast/float_node_spec.rb
+++ b/spec/rubocop/ast/float_node_spec.rb
@@ -10,16 +10,18 @@
   end
 
   describe '#sign?' do
+    subject { float_node.sign? }
+
     context 'explicit positive float' do
       let(:source) { '+42.0' }
 
-      it { is_expected.to be_sign }
+      it { is_expected.to be(true) }
     end
 
     context 'explicit negative float' do
       let(:source) { '-42.0' }
 
-      it { is_expected.to be_sign }
+      it { is_expected.to be(true) }
     end
   end
 
diff --git a/spec/rubocop/ast/int_node_spec.rb b/spec/rubocop/ast/int_node_spec.rb
index 677e7109b..47d1bfd10 100644
--- a/spec/rubocop/ast/int_node_spec.rb
+++ b/spec/rubocop/ast/int_node_spec.rb
@@ -10,16 +10,18 @@
   end
 
   describe '#sign?' do
+    subject { int_node.sign? }
+
     context 'explicit positive int' do
       let(:source) { '+42' }
 
-      it { is_expected.to be_sign }
+      it { is_expected.to be(true) }
     end
 
     context 'explicit negative int' do
       let(:source) { '-42' }
 
-      it { is_expected.to be_sign }
+      it { is_expected.to be(true) }
     end
   end
 
diff --git a/spec/rubocop/ast/rational_node_spec.rb b/spec/rubocop/ast/rational_node_spec.rb
index 8e27da8e8..a253ce395 100644
--- a/spec/rubocop/ast/rational_node_spec.rb
+++ b/spec/rubocop/ast/rational_node_spec.rb
@@ -10,16 +10,18 @@
   end
 
   describe '#sign?' do
+    subject { rational_node.sign? }
+
     context 'when explicit positive rational' do
       let(:source) { '+0.2r' }
 
-      it { is_expected.to be_sign }
+      it { is_expected.to be(true) }
     end
 
     context 'when explicit negative rational' do
       let(:source) { '-0.2r' }
 
-      it { is_expected.to be_sign }
+      it { is_expected.to be(true) }
     end
   end