diff --git a/doc/whats-new.rst b/doc/whats-new.rst
index 317c935995b..a9e8feb905c 100644
--- a/doc/whats-new.rst
+++ b/doc/whats-new.rst
@@ -61,6 +61,8 @@ New Features
   variables of a section at once, and shows the expanded attributes and data
   more compactly and indented below their variable (:pull:`11284`).
   By `Michael Niklas <https://github.com/headtr1ck>`_.
+- Use ``check_string_dtype()`` to detect variable-length strings in h5netcdf backend (:pull:`11789`).
+  By `Kai Mühlbauer <https://github.com/kmuehlbauer>`_.
 
 
 Breaking Changes
diff --git a/xarray/backends/h5netcdf_.py b/xarray/backends/h5netcdf_.py
index d2060976d01..18ade782764 100644
--- a/xarray/backends/h5netcdf_.py
+++ b/xarray/backends/h5netcdf_.py
@@ -297,8 +297,8 @@ def open_store_variable(self, name, var):
                 },
             )
         else:
-            vlen_dtype = h5py.check_dtype(vlen=var.dtype)
-            if vlen_dtype is str:
+            string_info = h5py.check_string_dtype(var.dtype)
+            if string_info is not None and string_info.length is None:
                 encoding["dtype"] = str
             else:
                 # xarray doesn't support writing arbitrary vlen dtypes yet, so