Shipbuilding and Repair Industry Trade Act of 1991

Shipbuilding and Repair Industry Trade Act of 1991 - Directs the Secretary of Commerce to annually determine and publish the net shipbuilding and repair subsidy provided, directly and indirectly, to each major shipbuilding and repair company in foreign countries meeting certain requirements. Requires the information submitted to the Secretary in connection with the determinations to be treated as proprietary if it meets certain requirements of the Tariff Act of 1930.

Requires each company to repay to its government the total value of the aggregate subsidy provided, plus interest. Directs the Secretary to: (1) require certification from both the company and the foreign government that the payments have occurred; and (2) if requested, verify the repayment.

Directs the Secretary, if a company has not complied, to direct the Commandant of the Coast Guard to collect an annual assessment on each vessel constructed or repaired by the company. Sets the amount of the assessment at the amount of the net subsidy, adjusted by partial repayments and increased by any previous unpaid assessment. Prohibits a vessel from entering a U.S. port until the assessment is paid in full.

Amends the Tariff Act of 1930 to impose an ad valorem duty on the cost of non-emergency equipment purchased or work done on a U.S.-documented vessel in a country that provides a subsidy to its ship construction and repair industry, as determined by the Secretary and the U.S. Trade Representative. (Current law imposed the same level of duty on equipment and repairs, making no reference to emergencies and not limiting the ad valorem duty to equipment or repairs done in a country that provides subsidies.)