FOR IMMEDIATE RELEASE Contact: Dave Thomas, VP Marketing and Planning

       (307) 432-7000

Great Lakes Aviation, Ltd. Reports July 2004 Traffic

CHEYENNE, Wyo., August 17, 2004 � Great Lakes Aviation, Ltd. (OTC Bulletin Board: GLUX � news) today announced preliminary passenger traffic results for the month of July.

Scheduled service generated 12,973,457 revenue passenger miles (RPM�s), a 9.7 percent increase from the same month last year.  Available seat miles (ASM�s) increased 3.6 percent to 29,364,365.  As a result, load factor increased 2.5 points to 44.2 percent.  Passengers carried increased 10.7 percent to 47,141 when compared with July 2003.

For the seven months ending July 31, 2004 compared to the same seven month period in 2003, revenue passenger miles (RPM�s) increased 18.5 percent to 77,958,391 while available seat miles (ASM�s) increased 3.8 percent to 194,588,067, resulting in a load factor of 40.1 percent for the year 2004 compared to 35.1 percent for the same seven month period in 2003.  The company carried 280,265 revenue passengers for the seven month period ending July 31, 2004, a 17.5 percent increase on a year-over-year basis.

JULY AND YEAR TO DATE STATISTICS

     July 2004 July 2003  Change

Passengers Enplaned 47,141 42,586 10.7%

Revenue Passenger Miles (000) 12,973 11,824  9.7%

Available Seat Miles (000) 29,364 28,355 3.6%

Load Factor 44.2% 41.7%    2.5 points

     YTD 2004 YTD 2003 Change

Passengers Enplaned 280,265 238,575 17.5%

Revenue Passenger Miles (000)  77,958 65,770 18.5%

Available Seat Miles (000) 194,588 187,536 3.8%

Load Factor 40.1% 35.1% 5.0 points

As of August 1, 2004, Great Lakes is providing scheduled passenger service at 36 airports in ten states with a fleet of Embraer EMB-120 Brasilias and Raytheon/Beech 1900D regional airliners.  A total of 186 weekday flights are scheduled at three hubs, with 176 flights at Denver, 4 flights at Minneapolis/St. Paul, and 6 flights at Phoenix. All scheduled flights are operated under the Great Lakes Airlines marketing identity in conjunction with code-share agreements with United Airlines and Frontier Airlines at their Denver hub.

Additional information is available on the company web site that may be accessed at www.greatlakesav.com