diff --git a/src/humanize/number.py b/src/humanize/number.py
index 52a5356a..14d09604 100644
--- a/src/humanize/number.py
+++ b/src/humanize/number.py
@@ -101,6 +101,10 @@ def ordinal(value: NumberOrString, gender: str = "male") -> str:
         ```pycon
         >>> ordinal(1)
         '1st'
+        >>> ordinal(-1)
+        '-1st'
+        >>> ordinal(-11)
+        '-11th'
         >>> ordinal(1002)
         '1002nd'
         >>> ordinal(103)
@@ -136,7 +140,10 @@ def ordinal(value: NumberOrString, gender: str = "male") -> str:
     except (TypeError, ValueError):
         return str(value)
     gender = "male" if gender == "male" else "female"
-    digit = 0 if value % 100 in (11, 12, 13) else value % 10
+    # Suffixes follow the absolute value. Python's % on a negative number
+    # is not the last digit, so -21 used to render as "-21th".
+    suffix_value = abs(value)
+    digit = 0 if suffix_value % 100 in (11, 12, 13) else suffix_value % 10
     return f"{value}{P_(*_ORDINAL_SUFFIXES[gender][digit])}"
 
 
diff --git a/tests/test_number.py b/tests/test_number.py
index 5fb12fa6..188c091b 100644
--- a/tests/test_number.py
+++ b/tests/test_number.py
@@ -25,6 +25,17 @@
         ("102", "102nd"),
         ("103", "103rd"),
         ("111", "111th"),
+        (-1, "-1st"),
+        (-2, "-2nd"),
+        (-3, "-3rd"),
+        (-11, "-11th"),
+        (-12, "-12th"),
+        (-13, "-13th"),
+        (-21, "-21st"),
+        (-22, "-22nd"),
+        (-23, "-23rd"),
+        (-101, "-101st"),
+        (-111, "-111th"),
         ("something else", "something else"),
         (None, "None"),
         (math.nan, "NaN"),