diff --git a/app/logical/sources/strategies/nico_seiga.rb b/app/logical/sources/strategies/nico_seiga.rb
index 0b9521648..544c00572 100644
--- a/app/logical/sources/strategies/nico_seiga.rb
+++ b/app/logical/sources/strategies/nico_seiga.rb
@@ -120,15 +120,15 @@ module Sources
 
       def normalized_url
         @normalized_url ||= begin
-          if url =~ %r!\Ahttp://lohas\.nicoseiga\.jp/o/[a-f0-9]+/\d+/(\d+)!
+          if url =~ %r!\Ahttps?://lohas\.nicoseiga\.jp/o/[a-f0-9]+/\d+/(\d+)!
             "http://seiga.nicovideo.jp/seiga/im#{$1}"
-          elsif url =~ %r{\Ahttp://lohas\.nicoseiga\.jp/priv/(\d+)\?e=\d+&h=[a-f0-9]+}i
+          elsif url =~ %r{\Ahttps?://lohas\.nicoseiga\.jp/priv/(\d+)\?e=\d+&h=[a-f0-9]+}i
             "http://seiga.nicovideo.jp/seiga/im#{$1}"
-          elsif url =~ %r{\Ahttp://lohas\.nicoseiga\.jp/priv/[a-f0-9]+/\d+/(\d+)}i
+          elsif url =~ %r{\Ahttps?://lohas\.nicoseiga\.jp/priv/[a-f0-9]+/\d+/(\d+)}i
             "http://seiga.nicovideo.jp/seiga/im#{$1}"
-          elsif url =~ %r{\Ahttp://lohas\.nicoseiga\.jp/priv/(\d+)}i
+          elsif url =~ %r{\Ahttps?://lohas\.nicoseiga\.jp/priv/(\d+)}i
             "http://seiga.nicovideo.jp/seiga/im#{$1}"
-          elsif url =~ %r{\Ahttp://lohas\.nicoseiga\.jp//?thumb/(\d+)}i
+          elsif url =~ %r{\Ahttps?://lohas\.nicoseiga\.jp//?thumb/(\d+)i?}i
             "http://seiga.nicovideo.jp/seiga/im#{$1}"
           elsif url =~ %r{/seiga/im\d+}
             url
diff --git a/test/unit/sources/nico_seiga_test.rb b/test/unit/sources/nico_seiga_test.rb
index 979f3c0c8..f5f70e501 100644
--- a/test/unit/sources/nico_seiga_test.rb
+++ b/test/unit/sources/nico_seiga_test.rb
@@ -49,6 +49,14 @@ module Sources
           @site_2.to_h
         end
       end
+
+      should "work for a https://lohas.nicoseiga.jp/thumb/${id}i url" do
+        site = Sources::Site.new("https://lohas.nicoseiga.jp/thumb/6844226i")
+        site.get
+
+        full_image_url = %r!https?://lohas.nicoseiga.jp/priv/[a-f0-9]{40}/[0-9]+/6844226!
+        assert_match(full_image_url, site.image_url)
+      end
     end
   end
 end