diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataLocationResolver.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataLocationResolver.java
index da54826bd112..e9c61dd5fd6b 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataLocationResolver.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataLocationResolver.java
@@ -16,9 +16,11 @@
 
 package org.springframework.boot.context.config;
 
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Deque;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
@@ -171,13 +173,17 @@ private Set<StandardConfigDataReference> getReferencesForDirectory(ConfigDataLoc
 			String directory, String profile) {
 		Set<StandardConfigDataReference> references = new LinkedHashSet<>();
 		for (String name : this.configNames) {
+			Deque<StandardConfigDataReference> referencesForName = new ArrayDeque<>();
 			for (PropertySourceLoader propertySourceLoader : this.propertySourceLoaders) {
 				for (String extension : propertySourceLoader.getFileExtensions()) {
 					StandardConfigDataReference reference = new StandardConfigDataReference(configDataLocation,
 							directory, directory + name, profile, extension, propertySourceLoader);
-					references.add(reference);
+					if (!referencesForName.contains(reference)) {
+						referencesForName.addFirst(reference);
+					}
 				}
 			}
+			references.addAll(referencesForName);
 		}
 		return references;
 	}
diff --git a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/config/ConfigDataEnvironmentPostProcessorIntegrationTests.java b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/config/ConfigDataEnvironmentPostProcessorIntegrationTests.java
index f9fab256442e..81f4869a0e4f 100644
--- a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/config/ConfigDataEnvironmentPostProcessorIntegrationTests.java
+++ b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/config/ConfigDataEnvironmentPostProcessorIntegrationTests.java
@@ -135,6 +135,13 @@ void runLoadsFileWithCustomName() {
 		assertThat(property).isEqualTo("frompropertiesfile");
 	}
 
+	@Test
+	void runWhenPropertiesAndYamlShouldPreferProperties() {
+		ConfigurableApplicationContext context = this.application.run();
+		String property = context.getEnvironment().getProperty("duplicate");
+		assertThat(property).isEqualTo("properties");
+	}
+
 	@Test
 	void runWhenMultipleCustomNamesLoadsEachName() {
 		ConfigurableApplicationContext context = this.application
diff --git a/spring-boot-project/spring-boot/src/test/resources/application.properties b/spring-boot-project/spring-boot/src/test/resources/application.properties
index 2f0172e0f2e3..2325ace12061 100644
--- a/spring-boot-project/spring-boot/src/test/resources/application.properties
+++ b/spring-boot-project/spring-boot/src/test/resources/application.properties
@@ -3,3 +3,4 @@ value: 1234
 my.property: fromapplicationproperties
 sample.app.test.prop: *
 my.placeholder: ${my.fallback}
+duplicate=properties
diff --git a/spring-boot-project/spring-boot/src/test/resources/application.yml b/spring-boot-project/spring-boot/src/test/resources/application.yml
new file mode 100644
index 000000000000..74fe76ca7cea
--- /dev/null
+++ b/spring-boot-project/spring-boot/src/test/resources/application.yml
@@ -0,0 +1 @@
+duplicate: yaml
\ No newline at end of file