--- a/python/setup.py
+++ b/python/setup.py
@@ -41,6 +41,29 @@ def is_gil_disabled():
   return sysconfig.get_config_var('Py_GIL_DISABLED')
 
 
+def run_pkg_config(section):
+  try:
+    output = subprocess.check_output([
+        'pkg-config', 'sentencepiece', '--{}'.format(section)
+    ])
+    if sys.version_info >= (3, 0, 0):
+      output = output.decode('utf-8')
+  except subprocess.CalledProcessError:
+    sys.stderr.write('Failed to find sentencepiece pkg-config\n')
+    sys.exit(1)
+  return output.strip().split()
+
+
+def is_sentencepiece_installed():
+  try:
+    subprocess.check_call([
+        'pkg-config', 'sentencepiece', '--libs'
+    ])
+    return True
+  except subprocess.CalledProcessError:
+    return False
+
+
 def find_abseil_lib(search_root):
   print('## searching abseil {}'.format(search_root))
   absl_libs = []
@@ -109,10 +132,15 @@ class build_ext_unix(_build_ext):
     cflags.extend(find_absl_include(is_msvc=False))
 
     if len(libs) == 0:
-      subprocess.check_call(['./build_bundled.sh', __version__])
-      cflags, libs = get_cflags_and_libs('./build/root')
-      abseil_libs = find_abseil_lib('./build/third_party')
-      cflags.extend(find_absl_include(is_msvc=False))
+      if is_sentencepiece_installed():
+        cflags = run_pkg_config('cflags')
+        libs = run_pkg_config('libs')
+        abseil_libs = []
+      else:
+        subprocess.check_call(['./build_bundled.sh', __version__])
+        cflags, libs = get_cflags_and_libs('./build/root')
+        abseil_libs = find_abseil_lib('./build/third_party')
+        cflags.extend(find_absl_include(is_msvc=False))
 
     # Fix compile on some versions of Mac OSX
     # See: https://github.com/neulab/xnmt/issues/199