Taht joined Rovio's external products division in 2014. A year later he was promoted to head of external products, before eventually becoming the mobile giant's head of games in 2016.
Company CEO Kati Levoranta will temporarily take on the role while the search for a permanent successor takes place.
"After three-and-a-half amazing years, working with some of the best games teams in the world, it's time to pass the hoodie and move on," said Taht.
"Over the last two years we have seen an astonishing change in our games when moving towards running our games as services and truly transitioned our games business to free-to-play. I will never forget that journey and the learnings I have been blessed with as head of games."