diff --git a/changelog/new_make_class_module_struct_definition_aware_of_numblock.md b/changelog/new_make_class_module_struct_definition_aware_of_numblock.md
new file mode 100644
index 000000000..4e8443fb9
--- /dev/null
+++ b/changelog/new_make_class_module_struct_definition_aware_of_numblock.md
@@ -0,0 +1 @@
+* [#205](https://github.com/rubocop/rubocop-ast/pull/205): Make class, module, and struct definitions aware of numblock. ([@koic][])
diff --git a/lib/rubocop/ast/node.rb b/lib/rubocop/ast/node.rb
index 89efc3c13..f1ada86dc 100644
--- a/lib/rubocop/ast/node.rb
+++ b/lib/rubocop/ast/node.rb
@@ -507,20 +507,20 @@ def guard_clause?
       # @deprecated Use `:class_constructor?`
       # @!method struct_constructor?(node = self)
       def_node_matcher :struct_constructor?, <<~PATTERN
-        (block (send #global_const?(:Struct) :new ...) _ $_)
+        ({block numblock} (send #global_const?(:Struct) :new ...) _ $_)
       PATTERN
 
       # @!method class_definition?(node = self)
       def_node_matcher :class_definition?, <<~PATTERN
         {(class _ _ $_)
          (sclass _ $_)
-         (block (send #global_const?({:Struct :Class}) :new ...) _ $_)}
+         ({block numblock} (send #global_const?({:Struct :Class}) :new ...) _ $_)}
       PATTERN
 
       # @!method module_definition?(node = self)
       def_node_matcher :module_definition?, <<~PATTERN
         {(module _ $_)
-         (block (send #global_const?(:Module) :new ...) _ $_)}
+         ({block numblock} (send #global_const?(:Module) :new ...) _ $_)}
       PATTERN
 
       # Some expressions are evaluated for their value, some for their side
diff --git a/spec/rubocop/ast/node_spec.rb b/spec/rubocop/ast/node_spec.rb
index eb87d2927..47b774d95 100644
--- a/spec/rubocop/ast/node_spec.rb
+++ b/spec/rubocop/ast/node_spec.rb
@@ -490,6 +490,21 @@ def details; end
         class_node = node.children.last
         expect(class_node.class_definition?).to eq(class_node.body)
       end
+
+      context 'when using numbered parameter', :ruby27 do
+        let(:src) do
+          <<~RUBY
+            Person = Struct.new(:name, :age) do
+              do_something _1
+            end
+          RUBY
+        end
+
+        it 'matches' do
+          class_node = node.children.last
+          expect(class_node.class_definition?).to eq(class_node.body)
+        end
+      end
     end
 
     context 'constant defined as Struct without block' do
@@ -514,6 +529,21 @@ def details; end
         class_node = node.children.last
         expect(class_node.class_definition?).to eq(class_node.body)
       end
+
+      context 'when using numbered parameter', :ruby27 do
+        let(:src) do
+          <<~RUBY
+            Person = Class.new do
+              do_something _1
+            end
+          RUBY
+        end
+
+        it 'matches' do
+          class_node = node.children.last
+          expect(class_node.class_definition?).to eq(class_node.body)
+        end
+      end
     end
 
     context 'namespaced class' do
@@ -593,6 +623,21 @@ def details; end
         module_node = node.children.last
         expect(module_node.module_definition?).to eq(module_node.body)
       end
+
+      context 'when using numbered parameter', :ruby27 do
+        let(:src) do
+          <<~RUBY
+            Person = Module.new do
+              do_something _1
+            end
+          RUBY
+        end
+
+        it 'matches' do
+          module_node = node.children.last
+          expect(module_node.module_definition?).to eq(module_node.body)
+        end
+      end
     end
 
     context 'prepend Module.new' do