diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,10 @@
 # Revision history for greskell-core
 
+## 0.1.2.6  -- 2019-06-10
+
+* Adapt test spec to `aeson-1.4.3.0` (#1).
+
+
 ## 0.1.2.5  -- 2019-03-31
 
 * Confirm test with `QuickCheck-2.13.1`.
diff --git a/greskell-core.cabal b/greskell-core.cabal
--- a/greskell-core.cabal
+++ b/greskell-core.cabal
@@ -1,5 +1,5 @@
 name:                   greskell-core
-version:                0.1.2.5
+version:                0.1.2.6
 author:                 Toshio Ito <debug.ito@gmail.com>
 maintainer:             Toshio Ito <debug.ito@gmail.com>
 license:                BSD3
@@ -48,7 +48,7 @@
   ghc-options:          -Wall -fno-warn-unused-imports "-with-rtsopts=-M512m"
   main-is:              Spec.hs
   -- default-extensions:   
-  other-extensions:     OverloadedStrings, NoMonomorphismRestriction
+  other-extensions:     OverloadedStrings, NoMonomorphismRestriction, CPP
   other-modules:        Data.Greskell.GreskellSpec,
                         Data.Greskell.GraphSONSpec,
                         Data.Greskell.GMapSpec,
diff --git a/test/Data/Greskell/GraphSONSpec.hs b/test/Data/Greskell/GraphSONSpec.hs
--- a/test/Data/Greskell/GraphSONSpec.hs
+++ b/test/Data/Greskell/GraphSONSpec.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE OverloadedStrings, NoMonomorphismRestriction #-}
+{-# LANGUAGE OverloadedStrings, NoMonomorphismRestriction, CPP #-}
 module Data.Greskell.GraphSONSpec (main,spec) where
 
 import Data.Aeson (object, (.=), ToJSON(..), FromJSON(..), Value(..))
@@ -76,6 +76,16 @@
                        ]
     parse input `shouldBe` Right (nonTypedGraphSON input)
 
+isParseTypeError :: String -- ^ expected type
+                 -> String -- ^ error message
+                 -> Bool -- ^ matched
+#if MIN_VERSION_aeson(1,4,3)
+isParseTypeError exp_type = isInfixOf ("parsing " <> exp_type <> " failed")
+#else
+isParseTypeError exp_type = isInfixOf ("expected " <> exp_type)
+#endif
+
+
 parseTypedGraphSON_spec :: Spec
 parseTypedGraphSON_spec = describe "parseTypedGraphSON" $ do
   let parse = parseEither parseTypedGraphSON
@@ -91,7 +101,7 @@
       got `shouldSatisfy` (isInfixOf "Expected @type")
     specify "typed JSON with valid @type field and invalid @value" $ do
       let (Left got) = parse (object ["@type" .= String "g:Int32", "@value" .= String "hoge"]) :: Either String (GraphSON Int32)
-      got `shouldSatisfy` (isInfixOf "expected Int32")
+      got `shouldSatisfy` isParseTypeError "Int32"
     specify "typed JSON with valid @type and @value" $ do
       let got = parse (object ["@type" .= String "g:Int32", "@value" .= Number 255]) :: Either String (GraphSON Int32)
       got `shouldBe` (Right $ typedGraphSON' "g:Int32" 255)
@@ -111,7 +121,7 @@
       let (Left got) = parse (object [ "@type" .= String "g:Array",
                                        "@value" .= Number 100
                                      ]) :: Either String (GraphSON (HashMap String String))
-      got `shouldSatisfy` (isInfixOf "expected HashMap")
+      got `shouldSatisfy` isParseTypeError "HashMap"
     specify "typed JSON with valid @type and @value" $ do
       let got = parse (object [ "@type" .= String "g:Map",
                                 "@value" .= object ["hoge" .= String "HOGE", "foo" .= String "FOO"]