diff --git a/mllib/src/main/scala/org/apache/spark/ml/regression/AFTSurvivalRegression.scala b/mllib/src/main/scala/org/apache/spark/ml/regression/AFTSurvivalRegression.scala
index 537f5ba3d4560..2f78dd30b3af7 100644
--- a/mllib/src/main/scala/org/apache/spark/ml/regression/AFTSurvivalRegression.scala
+++ b/mllib/src/main/scala/org/apache/spark/ml/regression/AFTSurvivalRegression.scala
@@ -229,7 +229,8 @@ class AFTSurvivalRegression @Since("1.6.0") (@Since("1.6.0") override val uid: S
 
     val instr = Instrumentation.create(this, dataset)
     instr.logParams(labelCol, featuresCol, censorCol, predictionCol, quantilesCol,
-      quantileProbabilities, fitIntercept, maxIter, tol, aggregationDepth)
+      fitIntercept, maxIter, tol, aggregationDepth)
+    instr.logNamedValue("quantileProbabilities.size", $(quantileProbabilities).length)
     instr.logNumFeatures(numFeatures)
 
     if (!$(fitIntercept) && (0 until numFeatures).exists { i =>