diff --git a/actionview/CHANGELOG.md b/actionview/CHANGELOG.md
index 729717608f9359426999675d53b03c4e99286086..fb39ac7508ee8392fce71bd0565261f68cff43fa 100644
--- a/actionview/CHANGELOG.md
+++ b/actionview/CHANGELOG.md
@@ -1 +1,6 @@
+*   Added an explicit error message, in `ActionView::PartialRenderer`
+    for partial `rendering`, when the value of option `as` has invalid characters.
+
+    *Angelo Capilleri*
+
 Please check [4-2-stable](https://github.com/rails/rails/blob/4-2-stable/actionview/CHANGELOG.md) for previous changes.
diff --git a/actionview/lib/action_view/renderer/partial_renderer.rb b/actionview/lib/action_view/renderer/partial_renderer.rb
index f627d5d40c2a8694d0c8a50e19bfb5cfb02bdcf9..610396506f256c078d727bbbf77482e610b84dfc 100644
--- a/actionview/lib/action_view/renderer/partial_renderer.rb
+++ b/actionview/lib/action_view/renderer/partial_renderer.rb
@@ -384,7 +384,7 @@ def setup(context, options, block)
       end
 
       if as = options[:as]
-        raise_invalid_identifier(as) unless as.to_s =~ /\A[a-z_]\w*\z/
+        raise_invalid_option_as(as) unless as.to_s =~ /\A[a-z_]\w*\z/
         as = as.to_sym
       end
 
@@ -530,11 +530,19 @@ def retrieve_variable(path, as)
     end
 
     IDENTIFIER_ERROR_MESSAGE = "The partial name (%s) is not a valid Ruby identifier; " +
-                               "make sure your partial name starts with a lowercase letter or underscore, " +
+                               "make sure your partial name starts with underscore, " +
+                               "and is followed by any combination of letters, numbers and underscores."
+
+    OPTION_AS_ERROR_MESSAGE  = "The value (%s) of the option `as` is not a valid Ruby identifier; " +
+                               "make sure it starts with lowercase letter, " +
                                "and is followed by any combination of letters, numbers and underscores."
 
     def raise_invalid_identifier(path)
       raise ArgumentError.new(IDENTIFIER_ERROR_MESSAGE % (path))
     end
+
+    def raise_invalid_option_as(as)
+      raise ArgumentError.new(OPTION_AS_ERROR_MESSAGE % (as))
+    end
   end
 end
diff --git a/actionview/test/template/render_test.rb b/actionview/test/template/render_test.rb
index 4e502bede9fa2e1f570a09f5929ef1ac48c42b81..e580a477a69630cfdfbf18c1580edd4407e17f38 100644
--- a/actionview/test/template/render_test.rb
+++ b/actionview/test/template/render_test.rb
@@ -175,14 +175,14 @@ def test_render_partial_with_locals_from_default
   def test_render_partial_with_invalid_name
     e = assert_raises(ArgumentError) { @view.render(:partial => "test/200") }
     assert_equal "The partial name (test/200) is not a valid Ruby identifier; " +
-      "make sure your partial name starts with a lowercase letter or underscore, " +
+      "make sure your partial name starts with underscore, " +
       "and is followed by any combination of letters, numbers and underscores.", e.message
   end
 
   def test_render_partial_with_missing_filename
     e = assert_raises(ArgumentError) { @view.render(:partial => "test/") }
     assert_equal "The partial name (test/) is not a valid Ruby identifier; " +
-      "make sure your partial name starts with a lowercase letter or underscore, " +
+      "make sure your partial name starts with underscore, " +
       "and is followed by any combination of letters, numbers and underscores.", e.message
   end
 
@@ -194,7 +194,21 @@ def test_render_partial_with_incompatible_object
   def test_render_partial_with_hyphen
     e = assert_raises(ArgumentError) { @view.render(:partial => "test/a-in") }
     assert_equal "The partial name (test/a-in) is not a valid Ruby identifier; " +
-      "make sure your partial name starts with a lowercase letter or underscore, " +
+      "make sure your partial name starts with underscore, " +
+      "and is followed by any combination of letters, numbers and underscores.", e.message
+  end
+
+  def test_render_partial_with_invalid_option_as
+    e = assert_raises(ArgumentError) { @view.render(:partial => "test/partial_only", :as => 'a-in') }
+    assert_equal "The value (a-in) of the option `as` is not a valid Ruby identifier; " +
+      "make sure it starts with lowercase letter, " +
+      "and is followed by any combination of letters, numbers and underscores.", e.message
+  end
+
+  def test_render_partial_with_hyphen_and_invalid_option_as
+    e = assert_raises(ArgumentError) { @view.render(:partial => "test/a-in", :as => 'a-in') }
+    assert_equal "The value (a-in) of the option `as` is not a valid Ruby identifier; " +
+      "make sure it starts with lowercase letter, " +
       "and is followed by any combination of letters, numbers and underscores.", e.message
   end