diff --git a/python/core/processing/qgsprocessingparameters.sip b/python/core/processing/qgsprocessingparameters.sip
index 36c98991b2c..3f094cf8e09 100644
--- a/python/core/processing/qgsprocessingparameters.sip
+++ b/python/core/processing/qgsprocessingparameters.sip
@@ -175,6 +175,8 @@ class QgsProcessingParameterDefinition
       sipType = sipType_QgsProcessingParameterRasterOutput;
     else if ( sipCpp->type() == "fileOut" )
       sipType = sipType_QgsProcessingParameterFileOutput;
+    else if ( sipCpp->type() == "folderOut" )
+      sipType = sipType_QgsProcessingParameterFolderOutput;
 %End
   public:
 
@@ -1344,6 +1346,32 @@ class QgsProcessingParameterFileOutput : QgsProcessingParameterDefinition
 
 };
 
+class QgsProcessingParameterFolderOutput : QgsProcessingParameterDefinition
+{
+%Docstring
+ A folder output parameter.
+.. versionadded:: 3.0
+%End
+
+%TypeHeaderCode
+#include "qgsprocessingparameters.h"
+%End
+  public:
+
+    QgsProcessingParameterFolderOutput( const QString &name, const QString &description = QString(),
+                                        const QVariant &defaultValue = QVariant(),
+                                        bool optional = false );
+%Docstring
+ Constructor for QgsProcessingParameterFolderOutput.
+%End
+
+    virtual QString type() const;
+    virtual bool isDestination() const;
+    virtual bool checkValueIsAcceptable( const QVariant &input, QgsProcessingContext *context = 0 ) const;
+
+
+};
+
 
 
 /************************************************************************
diff --git a/src/core/processing/qgsprocessingparameters.cpp b/src/core/processing/qgsprocessingparameters.cpp
index 972b147ca75..12f0475e700 100644
--- a/src/core/processing/qgsprocessingparameters.cpp
+++ b/src/core/processing/qgsprocessingparameters.cpp
@@ -1912,3 +1912,27 @@ void QgsProcessingParameterFileOutput::setFileFilter( const QString &fileFilter
 {
   mFileFilter = fileFilter;
 }
+
+QgsProcessingParameterFolderOutput::QgsProcessingParameterFolderOutput( const QString &name, const QString &description, const QVariant &defaultValue, bool optional )
+  : QgsProcessingParameterDefinition( name, description, defaultValue, optional )
+{}
+
+bool QgsProcessingParameterFolderOutput::checkValueIsAcceptable( const QVariant &input, QgsProcessingContext * ) const
+{
+  QVariant var = input;
+  if ( !var.isValid() )
+    return mFlags & FlagOptional;
+
+  if ( var.canConvert<QgsProperty>() )
+  {
+    return true;
+  }
+
+  if ( var.type() != QVariant::String )
+    return false;
+
+  if ( var.toString().isEmpty() )
+    return mFlags & FlagOptional;
+
+  return true;
+}
diff --git a/src/core/processing/qgsprocessingparameters.h b/src/core/processing/qgsprocessingparameters.h
index 7d52b742dd0..227dfd09d97 100644
--- a/src/core/processing/qgsprocessingparameters.h
+++ b/src/core/processing/qgsprocessingparameters.h
@@ -210,6 +210,8 @@ class CORE_EXPORT QgsProcessingParameterDefinition
       sipType = sipType_QgsProcessingParameterRasterOutput;
     else if ( sipCpp->type() == "fileOut" )
       sipType = sipType_QgsProcessingParameterFileOutput;
+    else if ( sipCpp->type() == "folderOut" )
+      sipType = sipType_QgsProcessingParameterFolderOutput;
     SIP_END
 #endif
 
@@ -1318,6 +1320,29 @@ class CORE_EXPORT QgsProcessingParameterFileOutput : public QgsProcessingParamet
     QString mFileFilter;
 };
 
+/**
+ * \class QgsProcessingParameterFolderOutput
+ * \ingroup core
+ * A folder output parameter.
+  * \since QGIS 3.0
+ */
+class CORE_EXPORT QgsProcessingParameterFolderOutput : public QgsProcessingParameterDefinition
+{
+  public:
+
+    /**
+     * Constructor for QgsProcessingParameterFolderOutput.
+     */
+    QgsProcessingParameterFolderOutput( const QString &name, const QString &description = QString(),
+                                        const QVariant &defaultValue = QVariant(),
+                                        bool optional = false );
+
+    QString type() const override { return QStringLiteral( "folderOut" ); }
+    bool isDestination() const override { return true; }
+    bool checkValueIsAcceptable( const QVariant &input, QgsProcessingContext *context = nullptr ) const override;
+
+};
+
 #endif // QGSPROCESSINGPARAMETERS_H
 
 
diff --git a/tests/src/core/testqgsprocessing.cpp b/tests/src/core/testqgsprocessing.cpp
index 094c18702df..0dce634a200 100644
--- a/tests/src/core/testqgsprocessing.cpp
+++ b/tests/src/core/testqgsprocessing.cpp
@@ -309,6 +309,7 @@ class TestQgsProcessing: public QObject
     void parameterFeatureSink();
     void parameterRasterOut();
     void parameterFileOut();
+    void parameterFolderOut();
     void checkParamValues();
     void combineLayerExtent();
     void processingFeatureSource();
@@ -2651,6 +2652,48 @@ void TestQgsProcessing::parameterFileOut()
   QCOMPARE( QgsProcessingParameters::parameterAsFileOutput( def.get(), params, context ), QStringLiteral( "default.txt" ) );
 }
 
+void TestQgsProcessing::parameterFolderOut()
+{
+  // setup a context
+  QgsProject p;
+  QgsProcessingContext context;
+  context.setProject( &p );
+
+  // not optional!
+  std::unique_ptr< QgsProcessingParameterFolderOutput > def( new QgsProcessingParameterFolderOutput( "non_optional", QString(), QString(), false ) );
+
+  QVERIFY( !def->checkValueIsAcceptable( false ) );
+  QVERIFY( !def->checkValueIsAcceptable( true ) );
+  QVERIFY( !def->checkValueIsAcceptable( 5 ) );
+  QVERIFY( def->checkValueIsAcceptable( "asdasd" ) );
+  QVERIFY( !def->checkValueIsAcceptable( "" ) );
+  QVERIFY( !def->checkValueIsAcceptable( QVariant() ) );
+
+  // should be OK with or without context - it's an output folder!
+  QVERIFY( def->checkValueIsAcceptable( "c:/Users/admin/Desktop/" ) );
+  QVERIFY( def->checkValueIsAcceptable( "c:/Users/admin/Desktop/", &context ) );
+
+  QVariantMap params;
+  params.insert( "non_optional", "c:/mine" );
+  QCOMPARE( QgsProcessingParameters::parameterAsFileOutput( def.get(), params, context ), QStringLiteral( "c:/mine" ) );
+
+  QCOMPARE( def->valueAsPythonString( QStringLiteral( "abc" ), context ), QStringLiteral( "'abc'" ) );
+  QCOMPARE( def->valueAsPythonString( QVariant::fromValue( QgsProperty::fromExpression( "\"a\"=1" ) ), context ), QStringLiteral( "QgsProperty.fromExpression('\"a\"=1')" ) );
+
+  // optional
+  def.reset( new QgsProcessingParameterFolderOutput( "optional", QString(), QString( "c:/junk" ), true ) );
+  QVERIFY( !def->checkValueIsAcceptable( false ) );
+  QVERIFY( !def->checkValueIsAcceptable( true ) );
+  QVERIFY( !def->checkValueIsAcceptable( 5 ) );
+  QVERIFY( def->checkValueIsAcceptable( "layer12312312" ) );
+  QVERIFY( def->checkValueIsAcceptable( "c:/Users/admin/Desktop/" ) );
+  QVERIFY( def->checkValueIsAcceptable( "" ) );
+  QVERIFY( def->checkValueIsAcceptable( QVariant() ) );
+
+  params.insert( "optional", QVariant() );
+  QCOMPARE( QgsProcessingParameters::parameterAsFileOutput( def.get(), params, context ), QStringLiteral( "c:/junk" ) );
+}
+
 void TestQgsProcessing::checkParamValues()
 {
   DummyAlgorithm a( "asd" );