diff --git a/pandas/core/arrays/string_.py b/pandas/core/arrays/string_.py
index b38eaa4072796..1be9af6e3d3b4 100644
--- a/pandas/core/arrays/string_.py
+++ b/pandas/core/arrays/string_.py
@@ -172,7 +172,7 @@ def __init__(
             warnings.warn(
                 "The 'pyarrow_numpy' storage option name is deprecated and will be "
                 'removed in pandas 3.0. Use \'pd.StringDtype(storage="pyarrow", '
-                "na_value-np.nan)' to construct the same dtype.\nOr enable the "
+                "na_value=np.nan)' to construct the same dtype.\nOr enable the "
                 "'pd.options.future.infer_string = True' option globally and use "
                 'the "str" alias as a shorthand notation to specify a dtype '
                 '(instead of "string[pyarrow_numpy]").',