diff --git a/autotest/gcore/pam.py b/autotest/gcore/pam.py
index 470c29c80ad5..1a9c7da8228d 100755
--- a/autotest/gcore/pam.py
+++ b/autotest/gcore/pam.py
@@ -423,6 +423,25 @@ def test_pam_13():
 
     gdal.SetConfigOption('GDAL_PAM_ENABLED', 'YES')
 
+###############################################################################
+# Test that existing PAM metadata is preserved when new is added
+# https://github.com/OSGeo/gdal/issues/1430
+
+
+def test_pam_metadata_preserved():
+
+    tmpfilename = '/vsimem/tmp.pnm'
+    ds = gdal.GetDriverByName('PNM').Create(tmpfilename, 1, 1)
+    ds.SetMetadataItem('foo', 'bar')
+    ds = None
+    ds = gdal.Open(tmpfilename)
+    ds.GetRasterBand(1).SetMetadataItem('bar', 'baz')
+    ds = None
+    ds = gdal.Open(tmpfilename)
+    assert ds.GetMetadataItem('foo') == 'bar'
+    assert ds.GetRasterBand(1).GetMetadataItem('bar') == 'baz'
+    ds = None
+    gdal.GetDriverByName('PNM').Delete(tmpfilename)
 
 ###############################################################################
 # Cleanup.
diff --git a/gdal/gcore/gdalpamdataset.cpp b/gdal/gcore/gdalpamdataset.cpp
index 9592d524bbc1..fcdd595ef6fb 100644
--- a/gdal/gcore/gdalpamdataset.cpp
+++ b/gdal/gcore/gdalpamdataset.cpp
@@ -418,7 +418,10 @@ CPLErr GDALPamDataset::XMLInit( CPLXMLNode *psTree, const char *pszUnused )
 /* -------------------------------------------------------------------- */
 /*      Apply any dataset level metadata.                               */
 /* -------------------------------------------------------------------- */
-    oMDMD.XMLInit( psTree, TRUE );
+    if( oMDMD.XMLInit( psTree, TRUE ) )
+    {
+        psPam->bHasMetadata = TRUE;
+    }
 
 /* -------------------------------------------------------------------- */
 /*      Try loading ESRI xml encoded GeodataXform.                      */