9 August 2007

Gran Tierra Energy To Announce Second Quarter 2007 Results Of Operations: Company To Host Conference Call On August 14, 2007 At 11:00 A.M. Eastern

CALGARY, CANADA, August 9, 2007 – Gran Tierra Energy Inc. (GTRE.OB) today announced that the Company’s senior management will discuss the company’s results of operations for the second quarter ended June 30, 2007 during a conference call scheduled for Tuesday, August 14, 2007, at 11:00 a.m. Eastern. The company’s financial results for the second quarter are scheduled to be released earlier that day.
What: Gran Tierra Energy Inc.’s Second Quarter 2007 Results Conference Call
When: Tuesday, August 14, 2007, 11:00 a.m. Eastern
Web cast address: http://www.streetevents.comhttp://www.fulldisclosure.com

Dial-in Numbers: (800) 599-9816 (domestic) or (617) 847-8705 (international), pass code # 64124577
Contact: Al Palombo, Cameron Associates, (212) 245-8800 Ext. 209,
If you are unable to participate, an audio replay of the call will be available beginning two hours after the call and will be available until 11:59 p.m. on August 21, 2007, by dialing (888286-8010 (domestic) or (617801-6888 (international) using confirmation pass code 78933699. An audio replay of the call will also be available on Gran Tierra’s web site, www.grantierra.com, until the next earnings call.
About Gran Tierra Energy Inc.:
Gran Tierra Energy Inc. is an international oil and gas exploration and production company, headquartered in Calgary, Canada, incorporated and traded in the United States and operating in South America. The Company holds interests in producing and prospective properties in Argentina, Colombia and Peru. To date, the Company has pursued a strategy that focuses on establishing a portfolio of producing properties, development and exploration opportunities, through selective acquisitions, to provide a base for future growth. Additional information concerning Gran Tierra Energy is available at www.grantierra.com. Investor inquiries may be directed to info@grantierra.com or 1-800-916-GTRE (4873).