diff --git a/spring-integration-sftp/src/main/java/org/springframework/integration/sftp/session/DefaultSftpSessionFactory.java b/spring-integration-sftp/src/main/java/org/springframework/integration/sftp/session/DefaultSftpSessionFactory.java
index f92c8f49f4..f2dbbebc50 100644
--- a/spring-integration-sftp/src/main/java/org/springframework/integration/sftp/session/DefaultSftpSessionFactory.java
+++ b/spring-integration-sftp/src/main/java/org/springframework/integration/sftp/session/DefaultSftpSessionFactory.java
@@ -25,6 +25,7 @@ import org.springframework.integration.file.remote.session.Session;
 import org.springframework.integration.file.remote.session.SessionFactory;
 import org.springframework.integration.file.remote.session.SharedSessionCapable;
 import org.springframework.util.Assert;
+import org.springframework.util.StreamUtils;
 import org.springframework.util.StringUtils;
 
 import com.jcraft.jsch.ChannelSftp.LsEntry;
@@ -42,6 +43,7 @@ import com.jcraft.jsch.UserInfo;
  * @author Oleg Zhurakousky
  * @author Gunnar Hillert
  * @author Gary Russell
+ * @author David Liu
  *
  * @since 2.0
  */
@@ -367,12 +369,12 @@ public class DefaultSftpSessionFactory implements SessionFactory<LsEntry>, Share
 
 		// private key
 		if (this.privateKey != null) {
-			String privateKeyFilePath = this.privateKey.getFile().getAbsolutePath();
+			byte[] keyByteArray = StreamUtils.copyToByteArray(this.privateKey.getInputStream());
 			if (StringUtils.hasText(this.privateKeyPassphrase)) {
-				this.jsch.addIdentity(privateKeyFilePath, this.privateKeyPassphrase);
+				this.jsch.addIdentity(this.user, keyByteArray, null, this.privateKeyPassphrase.getBytes());
 			}
 			else {
-				this.jsch.addIdentity(privateKeyFilePath);
+				this.jsch.addIdentity(this.user, keyByteArray, null, null);
 			}
 		}
 		com.jcraft.jsch.Session jschSession = this.jsch.getSession(this.user, this.host, this.port);
diff --git a/spring-integration-sftp/src/test/java/org/springframework/integration/sftp/session/SftpServerTests.java b/spring-integration-sftp/src/test/java/org/springframework/integration/sftp/session/SftpServerTests.java
index 3fe26d00af..910e4c2faf 100644
--- a/spring-integration-sftp/src/test/java/org/springframework/integration/sftp/session/SftpServerTests.java
+++ b/spring-integration-sftp/src/test/java/org/springframework/integration/sftp/session/SftpServerTests.java
@@ -30,7 +30,6 @@ import java.security.PublicKey;
 import java.security.spec.RSAPublicKeySpec;
 import java.util.Arrays;
 
-import com.jcraft.jsch.ChannelSftp.LsEntry;
 import org.apache.sshd.SshServer;
 import org.apache.sshd.common.NamedFactory;
 import org.apache.sshd.common.file.FileSystemView;
@@ -45,13 +44,17 @@ import org.apache.sshd.server.session.ServerSession;
 import org.apache.sshd.server.sftp.SftpSubsystem;
 import org.junit.Test;
 
+import org.springframework.core.io.ByteArrayResource;
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.integration.file.remote.session.Session;
 import org.springframework.integration.test.util.SocketUtils;
 import org.springframework.util.StreamUtils;
 
+import com.jcraft.jsch.ChannelSftp.LsEntry;
+
 /**
  * @author Gary Russell
+ * @author David Liu
  * @since 4.1
  *
  */
@@ -150,7 +153,8 @@ public class SftpServerTests {
 			f.setHost("localhost");
 			f.setPort(port);
 			f.setUser("user");
-			f.setPrivateKey(new ClassPathResource("id_rsa"));
+			InputStream stream = new ClassPathResource("id_rsa").getInputStream();
+			f.setPrivateKey(new ByteArrayResource(StreamUtils.copyToByteArray(stream)));
 			Session<LsEntry> session = f.getSession();
 			doTest(server, session);
 		}