diff --git a/.gitmodules b/.gitmodules
index 7f6c8f2b244b751a7c08c692ee6350735dfe5a91..72031ae442a7d58acd066da8f19efce23e5160a4 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -19,3 +19,6 @@
 [submodule "ThirdParty/cmake-modules"]
 	path = ThirdParty/cmake-modules
 	url = https://github.com/ufz/cmake-modules.git
+[submodule "Tests/Data"]
+	path = Tests/Data
+	url = https://github.com/ufz/ogs-data
diff --git a/Tests/Data b/Tests/Data
new file mode 160000
index 0000000000000000000000000000000000000000..0e399d3dc4e6f44998fe5456800f2b2c502a65f3
--- /dev/null
+++ b/Tests/Data
@@ -0,0 +1 @@
+Subproject commit 0e399d3dc4e6f44998fe5456800f2b2c502a65f3
diff --git a/scripts/cmake/SubmoduleSetup.cmake b/scripts/cmake/SubmoduleSetup.cmake
index f3d81e2d4d7fc423a1be9ad4db4b67fea6828d6b..5ffb0a1e0141ec722548b879c1ef02ca7e2c52af 100644
--- a/scripts/cmake/SubmoduleSetup.cmake
+++ b/scripts/cmake/SubmoduleSetup.cmake
@@ -12,6 +12,9 @@ set(REQUIRED_SUBMODULES
 	ThirdParty/tetgen
 	${OGS_ADDITIONAL_SUBMODULES_TO_CHECKOUT}
 )
+if(OGS_BUILD_TESTS)
+	list(APPEND REQUIRED_SUBMODULES Tests/Data)
+endif()
 
 foreach(SUBMODULE ${REQUIRED_SUBMODULES})
 	if(WIN32)
diff --git a/scripts/cmake/test/AddTest.cmake b/scripts/cmake/test/AddTest.cmake
index 58db2b22a4cd70e2b1b009fcde4a093902ab3f22..51ad99eae84d7ddafae2583a349491e1d2464305 100644
--- a/scripts/cmake/test/AddTest.cmake
+++ b/scripts/cmake/test/AddTest.cmake
@@ -31,9 +31,6 @@
 
 function (AddTest)
 
-	set(ExternalData_SOURCE_ROOT ${CMAKE_SOURCE_DIR}/../data)
-	set(ExternalData_BINARY_ROOT ${CMAKE_BINARY_DIR}/Tests/Data)
-
 	# parse arguments
 	set(options NONE)
 	set(oneValueArgs EXECUTABLE PATH NAME WRAPPER TESTER)
@@ -41,7 +38,7 @@ function (AddTest)
 	cmake_parse_arguments(AddTest "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
 
 	# TODO set to submodule
-	set(AddTest_SOURCE_PATH "${CMAKE_SOURCE_DIR}/../data/${AddTest_PATH}")
+	set(AddTest_SOURCE_PATH "${CMAKE_SOURCE_DIR}/Tests/Data/${AddTest_PATH}")
 	set(AddTest_BINARY_PATH "${CMAKE_BINARY_DIR}/Tests/Data/${AddTest_PATH}")
 	file(MAKE_DIRECTORY ${AddTest_BINARY_PATH})
 	file(TO_NATIVE_PATH "${AddTest_BINARY_PATH}" AddTest_BINARY_PATH_NATIVE)