Geology graduate Poirier was previously the vice president of corporate development at Hecla Mining and was an integral part of the team responsible for Hecla's acquisition of Aurizon Mines Ltd in 2013.
Before that, he had a 20 year career as a sell-side mining analyst at several Canadian investment firms and also has experience as a field geologist.
Otis president and chief executive Craig Lindsay said: "We are very pleased to welcome Don to our board of directors.
"His broad experience in the mining sector, which includes capital markets and mergers and acquisitions, coupled with his educational background, will add significant bench strength to Otis as we continue to develop the Kilgore project."
Poirier added: "I'm delighted to join the leadership team at Otis Gold. With a healthy balance sheet, the company is ideally positioned to continue with advanced work and development on several assets including the Kilgore Project where significant progress in the understanding of its geological potential has been made in the past two years."