diff --git a/tests/test_preprocessing.py b/tests/test_preprocessing.py
index 11aee6e..27363ec 100644
--- a/tests/test_preprocessing.py
+++ b/tests/test_preprocessing.py
@@ -1,7 +1,6 @@
 import numpy as np
 import pysptk
 import pytest
-import pyworld
 from nnmnkwii import preprocessing as P
 from nnmnkwii.datasets import FileSourceDataset, PaddedFileSourceDataset
 from nnmnkwii.preprocessing import (
@@ -22,6 +21,14 @@
 from packaging.version import Version
 from scipy.io import wavfile
 
+try:
+    import pyworld
+
+    pyworld_available = True
+except ValueError:
+    # ValueError: numpy.dtype size changed, may indicate binary incompatibility.
+    pyworld_available = False
+
 
 def _get_windows_set_bandmat():
     windows_set = [
@@ -271,6 +278,7 @@ def test_interp1d():
     assert np.all(if0 != 0)
 
 
+@pytest.mark.skipif(not pyworld_available, reason="pyworld is not available")
 def test_trim_remove_zeros_frames():
     fs, x = wavfile.read(example_audio_file())
     frame_period = 5
@@ -452,6 +460,7 @@ def test_dtw_frame_length_adjustment():
 @pytest.mark.skipif(
     Version(np.__version__) >= Version("2.0.0"), reason="numpy >= 2.0.0"
 )
+@pytest.mark.skipif(not pyworld_available, reason="pyworld is not available")
 def test_dtw_aligner():
     from nnmnkwii.preprocessing.alignment import DTWAligner, IterativeDTWAligner