diff --git a/monai/losses/barlow_twins.py b/monai/losses/barlow_twins.py
index 699594493c..dd38577eb3 100644
--- a/monai/losses/barlow_twins.py
+++ b/monai/losses/barlow_twins.py
@@ -78,7 +78,7 @@ def forward(self, input: torch.Tensor, target: torch.Tensor) -> torch.Tensor:
         c = torch.mm(input_norm.t(), target_norm) / batch_size  # input_norm.t() is FxB, target_norm is BxF so c is FxF
 
         # loss
-        c_diff = (c - torch.eye(c.size(0), device=c.device)).pow_(2)  # FxF
+        c_diff = (c - torch.eye(c.size(0), dtype=c.dtype, device=c.device)).pow_(2)  # FxF
         c_diff[~torch.eye(c.size(0), device=c.device).bool()] *= lambd_tensor
 
         return c_diff.sum()
diff --git a/tests/losses/test_barlow_twins_loss.py b/tests/losses/test_barlow_twins_loss.py
index 81f4032e0c..e41296bf18 100644
--- a/tests/losses/test_barlow_twins_loss.py
+++ b/tests/losses/test_barlow_twins_loss.py
@@ -104,6 +104,17 @@ def check_warning_raised(self):
         with self.assertWarns(Warning):
             BarlowTwinsLoss(lambd=5e-3, batch_size=1)
 
+    @parameterized.expand([(torch.float64,), (torch.float32,), (torch.bfloat16,), (torch.float16,)])
+    def test_preserves_input_dtype(self, dtype):
+        # The cross-correlation matrix `c` follows the input dtype, but `c - torch.eye(...)`
+        # used to silently upcast to float32 whenever dtype < float32, because torch.eye()
+        # was never given an explicit dtype and defaults to the global default (float32).
+        loss = BarlowTwinsLoss(lambd=5e-3)
+        i = torch.randn(4, 8, dtype=dtype)
+        j = torch.randn(4, 8, dtype=dtype)
+        output = loss(i, j)
+        self.assertEqual(output.dtype, dtype)
+
 
 if __name__ == "__main__":
     unittest.main()