diff --git a/lib/flgen/context.rb b/lib/flgen/context.rb
index 7438320..179fdb6 100644
--- a/lib/flgen/context.rb
+++ b/lib/flgen/context.rb
@@ -39,6 +39,10 @@ def define_macro(macro, value = nil)
       add_macro_definition(k, v, false)
     end
 
+    def undefine_macro(macro)
+      remove_macro(macro)
+    end
+
     def macros
       @macros ||= {}
     end
@@ -111,11 +115,19 @@ def add_macro_definition(macro, value, predefined)
     end
 
     def add_macro_argument(name, value)
-      arguments
-        .delete_if { |argument| argument.type == :define && argument.name == name }
+      arguments.delete_if { |arg| macro_definition?(arg, name) }
       add_compile_argument(Arguments::Define.new(name, value))
     end
 
+    def remove_macro(macro)
+      name = macro.to_sym
+      arguments.reject! { |arg| macro_definition?(arg, name) } && macros.delete(name)
+    end
+
+    def macro_definition?(arg, name)
+      arg.type == :define && arg.name == name
+    end
+
     def directory_already_added?(type, path)
       arguments
         .any? { |argument| argument.type == type && argument.path == path }
diff --git a/lib/flgen/file_list.rb b/lib/flgen/file_list.rb
index 50a2f3e..496beca 100644
--- a/lib/flgen/file_list.rb
+++ b/lib/flgen/file_list.rb
@@ -49,6 +49,10 @@ def define_macro(macro, value = nil)
       @context.define_macro(macro, value)
     end
 
+    def undefine_macro(macro)
+      @context.undefine_macro(macro)
+    end
+
     def macro?(macro)
       @context.macros.key?(macro.to_sym)
     end
@@ -126,9 +130,7 @@ def add_entry(path, from, raise_error, method_name, location)
     end
 
     def raise_no_entry_error(path, location, raise_error)
-      return unless raise_error
-
-      raise NoEntryError.new(path, location)
+      raise_error && (raise NoEntryError.new(path, location))
     end
 
     def glob_files(patterns, from, method_name, location)
diff --git a/spec/flgen/context_spec.rb b/spec/flgen/context_spec.rb
index 32f07c3..4e0b160 100644
--- a/spec/flgen/context_spec.rb
+++ b/spec/flgen/context_spec.rb
@@ -242,6 +242,31 @@ module piyo;
     end
   end
 
+  describe '#undefine_macro' do
+    it '定義済みマクロを無効化する' do
+      context.define_macro(:FOO)
+      context.define_macro('BAR=1')
+      context.define_macro(:BAZ)
+
+      context.undefine_macro(:QUX)
+      context.undefine_macro(:BAZ)
+      context.undefine_macro(:FOO)
+
+      expect(context.macros).to match(BAR: '1')
+    end
+
+    specify '事前定義済みマクロは無効化しない' do
+      options[:tool] = :vcs
+
+      context.define_macro(:FOO)
+      context.define_macro(:BAR)
+      context.undefine_macro(:FOO)
+      context.undefine_macro(:VCS)
+
+      expect(context.macros).to match(VCS: true, BAR: true)
+    end
+  end
+
   describe '事前定義済みマクロ' do
     context '対象ツールがVCSの場合' do
       specify ':VCSが定義される' do
diff --git a/spec/flgen/file_list_spec.rb b/spec/flgen/file_list_spec.rb
index dde184c..4f07738 100644
--- a/spec/flgen/file_list_spec.rb
+++ b/spec/flgen/file_list_spec.rb
@@ -1390,6 +1390,18 @@ def mock_glob(pattens, results)
     end
   end
 
+  describe '#undefine_macro' do
+    it 'マクロを無効化する' do
+      file_list = described_class.new(context, path)
+
+      expect(context).to receive(:undefine_macro).with(:FOO)
+      expect(context).to receive(:undefine_macro).with(:BAR)
+
+      file_list.undefine_macro(:FOO)
+      file_list.undefine_macro(:BAR)
+    end
+  end
+
   describe '#macro?/#macro_defined?' do
     let(:macros) do
       [:FOO, :BAR]