Driftnet Moratorium Enforcement Act of 1991

Driftnet Moratorium Enforcement Act of 1991 - Directs the President to certify to the Congress each nation: (1) whose nationals or vessels are known to engage in large-scale driftnet fishing; (2) that has not notified the United States that it will terminate large-scale driftnet fishing outside the exclusive economic zone of any nation by a certain date; and (3) whose vessels or nationals have not, by that date, ceased such fishing.

Deems certification that a nation has failed to give notice of its intent to cease driftnet fishing to be a certification under the Fishermen's Protective Act of 1967 (allowing banning importation of fish products).

Directs the President, on certification of failure to cease by the deadline, to prohibit the bringing or importation of fish and fish products from the country.

Authorizes the President to impose additional economic sanctions (including duties, import bans or restrictions, and fees or restrictions on services) if: (1) the U.S. ban on fish imports is insufficient to cause the nation to terminate large-scale driftnet fishing; or (2) a country retaliates as a result of a U.S. ban on fish imports.

Continues the fish import ban or additional sanctions until the nation completely ceases large-scale driftnet fishing by its nationals and vessels beyond the exclusive economic zone of any nation.