diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2777406..859f632 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,7 @@ This project adheres to [Semantic Versioning](http://semver.org/) and
 ### Fixed
 
 - `RDF.Date.equal_value?/2` did not handle timezones correctly
+- `-00:00` is a valid timezone offset on `RDF.DateTime`
 
 
 [Compare v0.5.1...HEAD](https://github.com/marcelotto/rdf-ex/compare/v0.5.1...HEAD)
diff --git a/lib/rdf/datatypes/date_time.ex b/lib/rdf/datatypes/date_time.ex
index 953f6e8..b6e1946 100644
--- a/lib/rdf/datatypes/date_time.ex
+++ b/lib/rdf/datatypes/date_time.ex
@@ -29,6 +29,14 @@ defmodule RDF.DateTime do
           _               -> super(value, opts)
         end
 
+      {:error, :invalid_format} ->
+        if String.ends_with?(value, "-00:00") do
+          String.replace_trailing(value, "-00:00", "Z")
+          |> convert(opts)
+        else
+          super(value, opts)
+        end
+
       {:error, :invalid_time} ->
         if String.contains?(value, "T24:00:00") do
           with [day, tz]  <- String.split(value, "T24:00:00", parts: 2),
@@ -43,6 +51,7 @@ defmodule RDF.DateTime do
         else
           super(value, opts)
         end
+
       _ ->
         super(value, opts)
     end
@@ -129,7 +138,7 @@ defmodule RDF.DateTime do
       nil ->
         nil
 
-      zone when zone in ["Z", "", "+00:00"] ->
+      zone when zone in ["Z", "", "+00:00", "-00:00"] ->
         canonical_lexical(literal.value)
 
       zone ->
diff --git a/test/unit/datatypes/date_time_test.exs b/test/unit/datatypes/date_time_test.exs
index cbe2229..6cda499 100644
--- a/test/unit/datatypes/date_time_test.exs
+++ b/test/unit/datatypes/date_time_test.exs
@@ -17,12 +17,14 @@ defmodule RDF.DateTimeTest do
       "2010-01-01T00:00:00.123456Z"      => { dt( "2010-01-01T00:00:00.123456Z") , nil                        , "2010-01-01T00:00:00.123456Z" },
       "2010-01-01T00:00:00"              => { dt( "2010-01-01T00:00:00")         , nil                        , "2010-01-01T00:00:00"  },
       "2010-01-01T00:00:00+00:00"        => { dt( "2010-01-01T00:00:00Z")        , "2010-01-01T00:00:00+00:00", "2010-01-01T00:00:00Z" },
+      "2010-01-01T00:00:00-00:00"        => { dt( "2010-01-01T00:00:00Z")        , "2010-01-01T00:00:00-00:00", "2010-01-01T00:00:00Z" },
       "2010-01-01T01:00:00+01:00"        => { dt( "2010-01-01T00:00:00Z")        , "2010-01-01T01:00:00+01:00", "2010-01-01T00:00:00Z" },
       "2009-12-31T23:00:00.42-01:00"     => { dt( "2010-01-01T00:00:00.42Z")     , "2009-12-31T23:00:00.42-01:00", "2010-01-01T00:00:00.42Z" },
       "2009-12-31T23:00:00-01:00"        => { dt( "2010-01-01T00:00:00Z")        , "2009-12-31T23:00:00-01:00", "2010-01-01T00:00:00Z" },
       "2009-12-31T24:00:00"              => { dt( "2010-01-01T00:00:00")         , "2009-12-31T24:00:00"      , "2010-01-01T00:00:00"  },
       "2009-12-31T24:00:00+00:00"        => { dt( "2010-01-01T00:00:00Z")        , "2009-12-31T24:00:00+00:00", "2010-01-01T00:00:00Z" },
-# TODO: DateTimes on Elixir versions < 1.7.2 don't handle negative years correctly, so we test this conditionally below
+      "2009-12-31T24:00:00-00:00"        => { dt( "2010-01-01T00:00:00Z")        , "2009-12-31T24:00:00-00:00", "2010-01-01T00:00:00Z" },
+# DateTimes on Elixir versions < 1.7.2 don't handle negative years correctly, so we test this conditionally below
 #      "-2010-01-01T00:00:00Z"            => { dt("-2010-01-01T00:00:00Z")        , nil, "-2010-01-01T00:00:00Z" },
     },
     invalid: ~w(
@@ -174,6 +176,7 @@ defmodule RDF.DateTimeTest do
     assert RDF.date_time(~N[2010-01-01T12:34:56])     |> DateTime.canonical_lexical_with_zone() == "2010-01-01T12:34:56"
     assert RDF.date_time("2010-01-01T12:34:56")       |> DateTime.canonical_lexical_with_zone() == "2010-01-01T12:34:56"
     assert RDF.date_time("2010-01-01T00:00:00+00:00") |> DateTime.canonical_lexical_with_zone() == "2010-01-01T00:00:00Z"
+    assert RDF.date_time("2010-01-01T00:00:00-00:00") |> DateTime.canonical_lexical_with_zone() == "2010-01-01T00:00:00Z"
     assert RDF.date_time("2010-01-01T01:00:00+01:00") |> DateTime.canonical_lexical_with_zone() == "2010-01-01T01:00:00+01:00"
     assert RDF.date_time("2010-01-01 01:00:00+01:00") |> DateTime.canonical_lexical_with_zone() == "2010-01-01T01:00:00+01:00"
   end
diff --git a/test/unit/datatypes/time_test.exs b/test/unit/datatypes/time_test.exs
index f04b14e..357800c 100644
--- a/test/unit/datatypes/time_test.exs
+++ b/test/unit/datatypes/time_test.exs
@@ -10,6 +10,7 @@ defmodule RDF.TimeTest do
       "00:00:00.1234Z"    => { {~T[00:00:00.1234], true }, nil                 , "00:00:00.1234Z" },
       "00:00:00.0000Z"    => { {~T[00:00:00.0000], true }, nil                 , "00:00:00.0000Z" },
       "00:00:00+00:00"    => { {~T[00:00:00], true }     , "00:00:00+00:00"    , "00:00:00Z" },
+      "00:00:00-00:00"    => { {~T[00:00:00], true }     , "00:00:00-00:00"    , "00:00:00Z" },
       "01:00:00+01:00"    => { {~T[00:00:00], true }     , "01:00:00+01:00"    , "00:00:00Z" },
       "23:00:00-01:00"    => { {~T[00:00:00], true }     , "23:00:00-01:00"    , "00:00:00Z" },
       "23:00:00.45-01:00" => { {~T[00:00:00.45], true }  , "23:00:00.45-01:00" , "00:00:00.45Z" },