diff --git a/lib/userializer/array_serializer.rb b/lib/userializer/array_serializer.rb
index 81ced10..d192e30 100644
--- a/lib/userializer/array_serializer.rb
+++ b/lib/userializer/array_serializer.rb
@@ -4,10 +4,11 @@ module USerializer
   class HeterogeneousArray < StandardError; end
 
   class ArraySerializer
-    def initialize(objs, opts = {})
+    def initialize(objs, opts = {}, embed_empty_array: false)
       @objs = objs.compact
       @opts = opts
       @meta = opts[:meta]
+      @embed_empty_array = embed_empty_array
 
       clss = @objs.map(&:class).uniq
       obj_class = clss.first
@@ -29,6 +30,7 @@ def initialize(objs, opts = {})
     end
 
     def merge_root(res, opts)
+      res[@root_key] ||= [] if @embed_empty_array
       @objs.each do |obj|
         serializer(obj, opts).merge_root(res, @root_key, false, opts)
       end
diff --git a/lib/userializer/composite_serializer.rb b/lib/userializer/composite_serializer.rb
index f442896..4010d09 100644
--- a/lib/userializer/composite_serializer.rb
+++ b/lib/userializer/composite_serializer.rb
@@ -64,7 +64,7 @@ def compose_objs(objs)
         if obj.is_a?(Hash) || !obj.is_a?(Enumerable)
           CompositeObject.new(obj, opts)
         else
-          ArraySerializer.new(obj, opts)
+          ArraySerializer.new(obj, opts, embed_empty_array: true)
         end
       end
     end
diff --git a/spec/userializer/composite_serializer_spec.rb b/spec/userializer/composite_serializer_spec.rb
index 9bbfd6a..df9a033 100644
--- a/spec/userializer/composite_serializer_spec.rb
+++ b/spec/userializer/composite_serializer_spec.rb
@@ -73,11 +73,12 @@ class Foo
     it do
       expect(
         USerializer::CompositeSerializer.new(
-          { key: foo, key_1: [foo] }
+          { key: foo, key_1: [foo], key_2: [] }
         ).to_hash
       ).to eq(
-        key:  { id: 1, bar: 'bar' },
-        key_1: [{ id: 1, bar: 'bar' }]
+        key:   { id: 1, bar: 'bar' },
+        key_1: [{ id: 1, bar: 'bar' }],
+        key_2: []
       )
     end
 
@@ -132,7 +133,7 @@ class Foo
           serializer: { bar: USerializer::RawSerializer }
         ).to_hash
       ).to eq(
-        key:  { id: 1, bar: 'bar' },
+        key: { id: 1, bar: 'bar' },
         bar: { buz: 'value' }
       )
     end