1 EXHIBIT 21 SUBSIDIARIES OF HORNBECK-LEEVAC MARINE SERVICES, INC. <Table> <Caption> STATE OF SUBSIDIARY NAME INCORPORATION NAME DOING BUSINESS AS Hornbeck Offshore Services, Inc. Delaware Hornbeck Offshore Services, Inc. HORNBECK-LEEVAC Marine Operators, Inc. Delaware HORNBECK-LEEVAC Marine Operators, Inc. LEEVAC Marine, Inc. Louisiana LEEVAC Marine, Inc. Energy Services Puerto Rico, Inc. Louisiana Energy Services Puerto Rico, Inc. </Table> II-1