diff --git a/src/main/java/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep.java b/src/main/java/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep.java
index 437cb2cf..e9af7c94 100644
--- a/src/main/java/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep.java
+++ b/src/main/java/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep.java
@@ -34,10 +34,12 @@
 import hudson.model.AutoCompletionCandidates;
 import hudson.model.Computer;
 import hudson.model.Executor;
+import hudson.model.Job;
 import hudson.model.Label;
 import hudson.model.Node;
 import hudson.model.Run;
 import hudson.model.TaskListener;
+import hudson.model.labels.LabelExpression;
 import hudson.util.FormValidation;
 import java.io.Serializable;
 import java.util.Set;
@@ -49,6 +51,7 @@
 import org.jenkinsci.plugins.workflow.steps.StepContext;
 import org.jenkinsci.plugins.workflow.steps.StepDescriptor;
 import org.jenkinsci.plugins.workflow.steps.StepExecution;
+import org.kohsuke.stapler.AncestorInPath;
 import org.kohsuke.stapler.DataBoundConstructor;
 import org.kohsuke.stapler.QueryParameter;
 
@@ -95,22 +98,12 @@ public final class ExecutorStep extends Step implements Serializable {
             return true;
         }
 
-        // TODO copied from AbstractProjectDescriptor
         public AutoCompletionCandidates doAutoCompleteLabel(@QueryParameter String value) {
-            AutoCompletionCandidates c = new AutoCompletionCandidates();
-            Jenkins j = Jenkins.getInstanceOrNull();
-            if (j != null) {
-                for (Label label : j.getLabels()) {
-                    if (label.getName().startsWith(value)) {
-                        c.add(label.getName());
-                    }
-                }
-            }
-            return c;
+            return LabelExpression.autoComplete(value);
         }
 
-        public FormValidation doCheckLabel(@QueryParameter String value) {
-            return AbstractProject.AbstractProjectDescriptor.validateLabelExpression(value, /* LabelValidator does not support Job */null);
+        public FormValidation doCheckLabel(@AncestorInPath Job<?, ?> job, @QueryParameter String value) {
+            return LabelExpression.validate(value, job);
         }
 
         @Override public Set<? extends Class<?>> getRequiredContext() {
diff --git a/src/main/resources/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep/config.jelly b/src/main/resources/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep/config.jelly
index 2486e9ab..4913974f 100644
--- a/src/main/resources/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep/config.jelly
+++ b/src/main/resources/org/jenkinsci/plugins/workflow/support/steps/ExecutorStep/config.jelly
@@ -26,6 +26,6 @@
 
 <j:jelly xmlns:j="jelly:core" xmlns:f="/lib/form">
     <f:entry title="Label" field="label">
-        <f:textbox/>
+        <f:textbox autoCompleteDelimChar=" "/>
     </f:entry>
 </j:jelly>