diff --git a/changelog/5819.bugfix.rst b/changelog/5819.bugfix.rst
new file mode 100644
index 00000000000..aa953429ad1
--- /dev/null
+++ b/changelog/5819.bugfix.rst
@@ -0,0 +1,2 @@
+Windows: Fix regression with conftest whose qualified name contains uppercase
+characters (introduced by #5792).
diff --git a/src/_pytest/pathlib.py b/src/_pytest/pathlib.py
index 0403b694737..d47ede20a25 100644
--- a/src/_pytest/pathlib.py
+++ b/src/_pytest/pathlib.py
@@ -11,7 +11,6 @@
 from os.path import expanduser
 from os.path import expandvars
 from os.path import isabs
-from os.path import normcase
 from os.path import sep
 from posixpath import sep as posix_sep
 
@@ -343,4 +342,4 @@ def unique_path(path):
 
     This is needed only for ``py.path.local``; ``pathlib.Path`` handles this
     natively with ``resolve()``."""
-    return type(path)(normcase(str(path.realpath())))
+    return type(path)(Path(str(path)).resolve())
diff --git a/testing/test_conftest.py b/testing/test_conftest.py
index 9888f5457f3..8395ab49511 100644
--- a/testing/test_conftest.py
+++ b/testing/test_conftest.py
@@ -292,6 +292,16 @@ def test_conftest_badcase(testdir):
     assert result.ret == ExitCode.NO_TESTS_COLLECTED
 
 
+def test_conftest_uppercase(testdir):
+    """Check conftest.py loading when directory casing is wrong."""
+    source = {"__init__.py": "", "Foo/conftest.py": "", "Foo/__init__.py": ""}
+    testdir.makepyfile(**source)
+
+    testdir.tmpdir.chdir()
+    result = testdir.runpytest()
+    assert result.ret == ExitCode.NO_TESTS_COLLECTED
+
+
 def test_no_conftest(testdir):
     testdir.makeconftest("assert 0")
     result = testdir.runpytest("--noconftest")