TYHEE PROVIDES UPDATE ON EXPLORATION, PERMITTING

(via Thenewswire.ca)

VANCOUVER, British Columbia (August 18, 2009)-- Tyhee Development Corp. (TSX Venture, TDC) today announced an update on exploration, permitting and preliminary feasibility work on its wholly owned Yellowknife Gold Project, NWT Canada.

Exploration crews have been mobilized to Clan Lake to map and prospect for extensions to existing gold zones and to identify additional gold zones within a newly recognized mineralized trend. Additionally, twenty one archival diamond drillholes have been selected for relogging and sampling based upon proximity to the known mineralization at Clan Lake and historic reports of gold in these drillholes. To date seven drillholes have been relogged and 635 m of this core has been selected for assaying. Another 1200 m of core in 12 holes remains to be evaluated. Only two of the twenty one drillholes were found to be unsuitable for further work.

Relogging and sampling the archival drill core will better define the size, grade and limits of the Clan Lake Main Zone. It is anticipated that, upon receipt of final assays, Tyhee will be in a position to update the gold resource on the Main Zone and outline a follow-up diamond drill plan.

Mapping and prospecting will examine a 6.5 km prospective trend that contains the 330, Pond, Main, Cranberry, Morel, Iceberg and Cub Zones with the purpose of;

a) better delineating these zones and any extensions with respect to their surface size and grade, and

b) identifying additional zones.

The Morel, Iceberg, and Cub Zones have not been mapped or sampled in detail, and were identified late in 2008. The Morel Zone appears to be similar to the Main and Cranberry Zones; it is 480 m long and up to 70 m wide (averaging 35 m) and is located 850 metres northeast of the Main Zone. Seven grab samples were collected from the Morel Zone in 2008 and all but one returned gold grades greater than 0.5 gpt. The Iceberg Zone is a poorly defined area of anomalous grab samples located 700 m northeast of the Morel Zone. The Cub Zone is located 3,000 m northeast of the Iceberg Zone, and is characterized by exceptionally high-grade gold values (>100 gpt) within metre-size flat-lying gently deformed quartz bodies that occur within a broader (10's metre) wide silicified domain. Eight of ten grab samples collected in late 2008 returned gold values ranging from between 0.1 and 100 gpt.

Work on the Preliminary Feasibility Study (PFS) has commenced with crews and equipment being mobilized for fieldwork, including diamond drilling, at Nicholas Lake and Ormsby. Drilling will also be conducted for site plan evaluation. Metallurgical samples are being collected for processing and environmental studies while hydrology and power studies are ongoing.

Permitting work is being conducted in conjunction with the above mentioned PFS.