diff --git a/import_export/resources.py b/import_export/resources.py
index <HASH>..<HASH> 100644
--- a/import_export/resources.py
+++ b/import_export/resources.py
@@ -328,7 +328,9 @@ class Resource(object):
             queryset = self.get_queryset()
         headers = self.get_export_headers()
         data = tablib.Dataset(headers=headers)
-        for obj in queryset:
+        # Iterate without the queryset cache, to avoid wasting memory when
+        # exporting large datasets.
+        for obj in queryset.iterator():
             data.append(self.export_resource(obj))
         return data
Bypass the queryset cache in Resource.export().

Without this, even moderately large exports (<I>k rows or more) can
quickly exhaust a system's memory.