diff --git a/dolphin/src/kitemviews/kfileitemmodel.cpp b/dolphin/src/kitemviews/kfileitemmodel.cpp
index f21edbf4a8..e2d0413a26 100644
--- a/dolphin/src/kitemviews/kfileitemmodel.cpp
+++ b/dolphin/src/kitemviews/kfileitemmodel.cpp
@@ -1036,6 +1036,14 @@ void KFileItemModel::insertItems(QList<ItemData*>& newItems)
 
     m_groups.clear();
 
+    if (m_naturalSorting) {
+        // Natural sorting of items can be very slow. However, it becomes much
+        // faster if the input sequence is already mostly sorted. Therefore, we
+        // first sort 'newItems' according to the QStrings returned by
+        // KFileItem::text() using QString::operator<(), which is quite fast.
+        parallelMergeSort(newItems.begin(), newItems.end(), nameLessThan, QThread::idealThreadCount());
+    }
+
     sort(newItems.begin(), newItems.end());
 
 #ifdef KFILEITEMMODEL_DEBUG
diff --git a/dolphin/src/kitemviews/kfileitemmodel.h b/dolphin/src/kitemviews/kfileitemmodel.h
index d005705492..4b50477d98 100644
--- a/dolphin/src/kitemviews/kfileitemmodel.h
+++ b/dolphin/src/kitemviews/kfileitemmodel.h
@@ -349,6 +349,12 @@ private:
 
     QHash<QByteArray, QVariant> retrieveData(const KFileItem& item, const ItemData* parent) const;
 
+    /**
+     * @return True if \a a has a KFileItem whose text is 'less than' the one
+     *         of \a b according to QString::operator<(const QString&).
+     */
+    static bool nameLessThan(const ItemData* a, const ItemData* b);
+
     /**
      * @return True if the item-data \a a should be ordered before the item-data
      *         \b. The item-data may have different parent-items.
@@ -485,6 +491,12 @@ private:
     friend class DolphinPart;                  // Accesses m_dirLister
 };
 
+inline bool KFileItemModel::nameLessThan(const ItemData* a, const ItemData* b)
+{
+    return a->item.text() < b->item.text();
+}
+
+
 inline bool KFileItemModel::isChildItem(int index) const
 {
     if (m_itemData.at(index)->parent) {