FOR IMMEDIATE RELEASE Contact: Michael Matthews, VP Finance/CFO

       (307) 432-7000

Great Lakes Aviation, Ltd. Reports May 2005 Traffic

CHEYENNE, Wyo., June 7, 2005 � Great Lakes Aviation, Ltd. (OTC Bulletin Board: GLUX.OB � news) today announced preliminary passenger traffic results for the month of May.

Scheduled service generated 9,621,000 revenue passenger miles (RPM�s), a 7.5 percent decrease from the same month last year. Available seat miles (ASM�s) decreased 7.7 percent to 23,738,000.  As a result, load factor increased 0.1 points to 40.5 percent. Passengers carried decreased 4.6 percent to 36,245 when compared to May 2004. Preliminary revenue per available seat mile (RASM) increased 8.4 % from 22.57 cents to 24.47 cents.

For the five months ending May 31, 2005 compared to the same five month period in 2004, revenue passenger miles (RPM�s) decreased 12.9 percent to 46,097,000 and available seat miles (ASM�s) decreased 12.9 percent to 111,541,000, resulting in a load factor of 41.3 percent for the year 2005 compared to 38.5 percent for the same five month period in 2004. The company carried 172,018 revenue passengers for the five month period ending May 31, 2005, a 9.3 percent decrease from the prior year.  Preliminary revenue per available seat mile (RASM) increased 15.4% from 20.83 cents to 24.04 cents on a year-over-year basis.

Service between Phoenix and both Kingman and Prescott, Arizona began on June 5^th.

MAY 2005 AND YEAR TO DATE STATISTICS

May 2005 May 2004 Change

Passengers Enplaned  36,245   38,000   (4.6%)

Revenue Passenger Miles (000) 9,621 10,399   (7.5%)

Available Seat Miles (000) 23,738   25,713    (7.7%)

Load Factor    40.5%   40.4%   0.1 points

RASM (cents)   24.47  22.57  8.4%

YTD 2005 YTD 2004 Change

Passengers Enplaned  172,018 189,726 (9.3%)

Revenue Passenger Miles (000) 46,097   52,947  (12.9%)

Available Seat Miles (000) 111,541 137,518 (18.9%)

Load Factor    41.3%  38.5%    2.8 points

RASM (cents)   24.04  20.83  15.4%

Great Lakes is providing scheduled passenger service at 39 airports in ten states with a fleet of Embraer EMB-120 Brasilias and Raytheon/Beech 1900D regional airliners. A total of 201 weekday flights are scheduled at three hubs, with 167 flights at Denver, 8 flights at Albuquerque, and 26 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 the Denver International Airport hub.

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