diff --git a/gplearn/genetic.py b/gplearn/genetic.py
index 54a90ee4..5d32e1f2 100644
--- a/gplearn/genetic.py
+++ b/gplearn/genetic.py
@@ -551,9 +551,9 @@ def fit(self, X, y, sample_weight=None):
             # Find the best individuals in the final generation
             fitness = np.array(fitness)
             if self._metric.greater_is_better:
-                hall_of_fame = fitness.argsort()[::-1][:self.hall_of_fame]
+                hall_of_fame = fitness.argsort(kind="stable")[::-1][:self.hall_of_fame]
             else:
-                hall_of_fame = fitness.argsort()[:self.hall_of_fame]
+                hall_of_fame = fitness.argsort(kind="stable")[:self.hall_of_fame]
             evaluation = np.array([gp.execute(X) for gp in
                                    [self._programs[-1][i] for
                                     i in hall_of_fame]])