diff --git a/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala b/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala
index 6648e78d8eafa..f01ca1a1cce38 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/classification/DecisionTreeClassifier.scala
@@ -91,7 +91,7 @@ class DecisionTreeClassifier @Since("1.4.0") (
 
   /** @group setParam */
   @Since("1.4.0")
-  override def setImpurity(value: String): this.type = set(impurity, value)
+  def setImpurity(value: String): this.type = set(impurity, value)
 
   /** @group setParam */
   @Since("1.6.0")
diff --git a/mllib/src/main/scala/org/apache/spark/ml/classification/GBTClassifier.scala b/mllib/src/main/scala/org/apache/spark/ml/classification/GBTClassifier.scala
index 62c6bdbdeb285..96367f117c2d6 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/classification/GBTClassifier.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/classification/GBTClassifier.scala
@@ -110,7 +110,7 @@ class GBTClassifier @Since("1.4.0") (
    * @group setParam
    */
   @Since("1.4.0")
-  override def setImpurity(value: String): this.type = {
+  def setImpurity(value: String): this.type = {
     logWarning("GBTClassifier.setImpurity should NOT be used")
     this
   }
diff --git a/mllib/src/main/scala/org/apache/spark/ml/classification/RandomForestClassifier.scala b/mllib/src/main/scala/org/apache/spark/ml/classification/RandomForestClassifier.scala
index 57132381b6474..66799a55ec647 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/classification/RandomForestClassifier.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/classification/RandomForestClassifier.scala
@@ -93,7 +93,7 @@ class RandomForestClassifier @Since("1.4.0") (
 
   /** @group setParam */
   @Since("1.4.0")
-  override def setImpurity(value: String): this.type = set(impurity, value)
+  def setImpurity(value: String): this.type = set(impurity, value)
 
   // Parameters from TreeEnsembleParams:
 
diff --git a/mllib/src/main/scala/org/apache/spark/ml/regression/DecisionTreeRegressor.scala b/mllib/src/main/scala/org/apache/spark/ml/regression/DecisionTreeRegressor.scala
index c9de85de42fa5..b076b41387baf 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/regression/DecisionTreeRegressor.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/regression/DecisionTreeRegressor.scala
@@ -90,7 +90,7 @@ class DecisionTreeRegressor @Since("1.4.0") (@Since("1.4.0") override val uid: S
 
   /** @group setParam */
   @Since("1.4.0")
-  override def setImpurity(value: String): this.type = set(impurity, value)
+  def setImpurity(value: String): this.type = set(impurity, value)
 
   /** @group setParam */
   @Since("1.6.0")
diff --git a/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala b/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala
index 07f88d8d5f84d..87c016af5b8d4 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/regression/GBTRegressor.scala
@@ -110,7 +110,7 @@ class GBTRegressor @Since("1.4.0") (@Since("1.4.0") override val uid: String)
    * @group setParam
    */
   @Since("1.4.0")
-  override def setImpurity(value: String): this.type = {
+  def setImpurity(value: String): this.type = {
     logWarning("GBTRegressor.setImpurity should NOT be used")
     this
   }
diff --git a/mllib/src/main/scala/org/apache/spark/ml/regression/RandomForestRegressor.scala b/mllib/src/main/scala/org/apache/spark/ml/regression/RandomForestRegressor.scala
index 66d57ad6c4348..c9a8b95c14e16 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/regression/RandomForestRegressor.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/regression/RandomForestRegressor.scala
@@ -92,7 +92,7 @@ class RandomForestRegressor @Since("1.4.0") (@Since("1.4.0") override val uid: S
 
   /** @group setParam */
   @Since("1.4.0")
-  override def setImpurity(value: String): this.type = set(impurity, value)
+  def setImpurity(value: String): this.type = set(impurity, value)
 
   // Parameters from TreeEnsembleParams:
 
diff --git a/mllib/src/main/scala/org/apache/spark/ml/tree/treeParams.scala b/mllib/src/main/scala/org/apache/spark/ml/tree/treeParams.scala
index f1e3836ebe476..b3ca86b866374 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/tree/treeParams.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/tree/treeParams.scala
@@ -226,13 +226,6 @@ private[ml] trait TreeClassifierParams extends Params {
 
   setDefault(impurity -> "gini")
 
-  /**
-   * @deprecated This method is deprecated and will be removed in 3.0.0.
-   * @group setParam
-   */
-  @deprecated("This method is deprecated and will be removed in 3.0.0.", "2.1.0")
-  def setImpurity(value: String): this.type = set(impurity, value)
-
   /** @group getParam */
   final def getImpurity: String = $(impurity).toLowerCase(Locale.ROOT)
 
@@ -273,13 +266,6 @@ private[ml] trait HasVarianceImpurity extends Params {
 
   setDefault(impurity -> "variance")
 
-  /**
-   * @deprecated This method is deprecated and will be removed in 3.0.0.
-   * @group setParam
-   */
-  @deprecated("This method is deprecated and will be removed in 3.0.0.", "2.1.0")
-  def setImpurity(value: String): this.type = set(impurity, value)
-
   /** @group getParam */
   final def getImpurity: String = $(impurity).toLowerCase(Locale.ROOT)
 
diff --git a/project/MimaExcludes.scala b/project/MimaExcludes.scala
index e35e74aa33045..09a324b7c7a4c 100644
--- a/project/MimaExcludes.scala
+++ b/project/MimaExcludes.scala
@@ -36,21 +36,26 @@ object MimaExcludes {
 
   // Exclude rules for 3.0.x
   lazy val v30excludes = v24excludes ++ Seq(
+
+    // [SPARK-26127] Remove deprecated setImpurity from tree regression and classification models
+    ProblemFilters.exclude[DirectMissingMethodProblem]("org.apache.spark.ml.classification.DecisionTreeClassificationModel.setImpurity"),
+    ProblemFilters.exclude[DirectMissingMethodProblem]("org.apache.spark.ml.classification.RandomForestClassificationModel.setImpurity"),
+    ProblemFilters.exclude[DirectMissingMethodProblem]("org.apache.spark.ml.classification.GBTClassificationModel.setImpurity"),
+    ProblemFilters.exclude[DirectMissingMethodProblem]("org.apache.spark.ml.regression.DecisionTreeRegressionModel.setImpurity"),
+    ProblemFilters.exclude[DirectMissingMethodProblem]("org.apache.spark.ml.regression.GBTRegressionModel.setImpurity"),
+    ProblemFilters.exclude[DirectMissingMethodProblem]("org.apache.spark.ml.regression.RandomForestRegressionModel.setImpurity"),
+
     // [SPARK-26090] Resolve most miscellaneous deprecation and build warnings for Spark 3 
     ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.mllib.stat.test.BinarySampleBeanInfo"),
     ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.mllib.regression.LabeledPointBeanInfo"),
     ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.ml.feature.LabeledPointBeanInfo"),
 
     // [SPARK-25959] GBTClassifier picks wrong impurity stats on loading
-    ProblemFilters.exclude[IncompatibleResultTypeProblem]("org.apache.spark.ml.classification.GBTClassificationModel.setImpurity"),
     ProblemFilters.exclude[InheritedNewAbstractMethodProblem]("org.apache.spark.ml.tree.HasVarianceImpurity.org$apache$spark$ml$tree$HasVarianceImpurity$_setter_$impurity_="),
     ProblemFilters.exclude[InheritedNewAbstractMethodProblem]("org.apache.spark.ml.tree.HasVarianceImpurity.org$apache$spark$ml$tree$HasVarianceImpurity$_setter_$impurity_="),
     ProblemFilters.exclude[InheritedNewAbstractMethodProblem]("org.apache.spark.ml.tree.HasVarianceImpurity.org$apache$spark$ml$tree$HasVarianceImpurity$_setter_$impurity_="),
     ProblemFilters.exclude[InheritedNewAbstractMethodProblem]("org.apache.spark.ml.tree.HasVarianceImpurity.org$apache$spark$ml$tree$HasVarianceImpurity$_setter_$impurity_="),
     ProblemFilters.exclude[InheritedNewAbstractMethodProblem]("org.apache.spark.ml.tree.HasVarianceImpurity.org$apache$spark$ml$tree$HasVarianceImpurity$_setter_$impurity_="),
-    ProblemFilters.exclude[IncompatibleResultTypeProblem]("org.apache.spark.ml.regression.DecisionTreeRegressionModel.setImpurity"),
-    ProblemFilters.exclude[IncompatibleResultTypeProblem]("org.apache.spark.ml.regression.GBTRegressionModel.setImpurity"),
-    ProblemFilters.exclude[IncompatibleResultTypeProblem]("org.apache.spark.ml.regression.RandomForestRegressionModel.setImpurity"),
 
     // [SPARK-25908][CORE][SQL] Remove old deprecated items in Spark 3
     ProblemFilters.exclude[DirectMissingMethodProblem]("org.apache.spark.BarrierTaskContext.isRunningLocally"),