diff --git a/dwave/system/samplers/leap_hybrid_sampler.py b/dwave/system/samplers/leap_hybrid_sampler.py
index fb331a39..a466e4c3 100644
--- a/dwave/system/samplers/leap_hybrid_sampler.py
+++ b/dwave/system/samplers/leap_hybrid_sampler.py
@@ -37,6 +37,7 @@
 
     bqm_to_file = FileView
 
+from dimod.discrete.discrete_quadratic_model import DiscreteQuadraticModel
 from dwave.cloud import Client
 from dwave.system.utilities import classproperty, FeatureFlags
 
@@ -465,6 +466,8 @@ def sample_dqm(self, dqm, time_limit=None, compress=False, compressed=None, **kw
             See the example in :class:`LeapHybridDQMSampler`.
 
         """
+        if not isinstance(dqm, DiscreteQuadraticModel):
+            raise TypeError(f"Expecting DiscreteQuadraticModel object, got {type(dqm)}")
         if time_limit is None:
             time_limit = self.min_time_limit(dqm)
         elif time_limit < self.min_time_limit(dqm):
diff --git a/tests/test_leaphybriddqmsolver.py b/tests/test_leaphybriddqmsolver.py
index 28ce1335..22adad26 100644
--- a/tests/test_leaphybriddqmsolver.py
+++ b/tests/test_leaphybriddqmsolver.py
@@ -54,6 +54,7 @@ def get_solver(self, *args, **kwargs):
             sampler = LeapHybridDQMSampler()
 
             dqm = dimod.DQM()
+            bqm = dimod.BinaryQuadraticModel('SPIN')
 
         with self.assertRaises(ValueError):
             sampler.sample_dqm(dqm, time_limit=1)
@@ -61,6 +62,9 @@ def get_solver(self, *args, **kwargs):
         with self.assertRaises(ValueError):
             sampler.sample_dqm(dqm, time_limit=10000000)
 
+        with self.assertRaises(TypeError):
+            sampler.sample_dqm(bqm)
+
     def test_DQM_subclass_without_serialization_can_be_sampled(self):
         """Test that DQM subclasses that do not implement serialization can
         still be sampled by LeapHybridDQMSampler.