Llyn Nantlle Uchaf (Welsh for 'Upper Nantlle Lake') is a lake in the Nantlle Valley, Gwynedd, Wales.

The lake forms the foreground in Richard Wilson's painting "Snowdon from Llyn Nantlle".

[1] Llyn Nantlle Isaf (Lower Nantlle Lake) no longer exists as it was drained to protect the slate works.

[2]