When you create the QTreeWidgetItem, do not set the text or icon.

Instead, create a QWidget that contains 2 QLabels (one for the icon, one for the text), then use the QTreeWidget::setItemWidget method to associate the QWidget with the QTreeWidgetItem.

When you see the mousePressEvent that starts the drag, get the QTreeWidgetItem *drag_item that's under the mouse by calling QTreeWidget::itemAt(event->pos()).

When creating the QDrag, create the pixmap by doing something like this:

QWidget *w = itemWidget(drag_item,0);
QPixmap pixmap(w->size());
w->render(&pixmap);
QDrag *drag = new QDrag;
drag->setPixmap(pixmap);