diff --git a/src/gt4py/next/program_processors/runners/gtfn.py b/src/gt4py/next/program_processors/runners/gtfn.py
index 12f5f34a7e..6bdb19a819 100644
--- a/src/gt4py/next/program_processors/runners/gtfn.py
+++ b/src/gt4py/next/program_processors/runners/gtfn.py
@@ -15,6 +15,7 @@
 import diskcache
 import factory
 import filelock
+import numpy as np
 
 import gt4py._core.definitions as core_defs
 import gt4py.next.allocators as next_allocators
@@ -34,6 +35,9 @@ def convert_arg(arg: Any) -> Any:
         arr = arg.ndarray
         origin = getattr(arg, "__gt_origin__", tuple([0] * len(arg.domain)))
         return arr, origin
+    if isinstance(arg, np.bool_):
+        # nanobind does not support implicit conversion of `np.bool` to `bool`
+        return bool(arg)
     else:
         return arg
 
diff --git a/tests/next_tests/integration_tests/feature_tests/ffront_tests/test_execution.py b/tests/next_tests/integration_tests/feature_tests/ffront_tests/test_execution.py
index a042c60709..1dbf0ff0a7 100644
--- a/tests/next_tests/integration_tests/feature_tests/ffront_tests/test_execution.py
+++ b/tests/next_tests/integration_tests/feature_tests/ffront_tests/test_execution.py
@@ -7,8 +7,10 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
 from functools import reduce
+
 import numpy as np
 import pytest
+
 import gt4py.next as gtx
 from gt4py.next import (
     astype,
@@ -21,9 +23,9 @@
     int64,
     minimum,
     neighbor_sum,
+    utils as gt_utils,
 )
 from gt4py.next.ffront.experimental import as_offset
-from gt4py.next import utils as gt_utils
 
 from next_tests.integration_tests import cases
 from next_tests.integration_tests.cases import (
@@ -31,6 +33,7 @@
     E2V,
     V2E,
     E2VDim,
+    Edge,
     IDim,
     Ioff,
     JDim,
@@ -38,7 +41,6 @@
     Koff,
     V2EDim,
     Vertex,
-    Edge,
     cartesian_case,
     unstructured_case,
     unstructured_case_3d,
@@ -196,6 +198,21 @@ def testee(a: int32) -> cases.VField:
     )
 
 
+def test_np_bool_scalar_arg(unstructured_case):
+    """Test scalar argument being turned into 0-dim field."""
+
+    @gtx.field_operator
+    def testee(a: gtx.bool) -> cases.VBoolField:
+        return broadcast(not a, (Vertex,))
+
+    a = np.bool_(True)  # explicitly using a np.bool
+
+    ref = np.full([unstructured_case.default_sizes[Vertex]], not a, dtype=np.bool_)
+    out = cases.allocate(unstructured_case, testee, cases.RETURN)()
+
+    cases.verify(unstructured_case, testee, a, out=out, ref=ref)
+
+
 def test_nested_scalar_arg(unstructured_case):
     @gtx.field_operator
     def testee_inner(a: int32) -> cases.VField: