Kukushkin, ranked 88th in the world and appearing in his first ATP final, upended the world No. 10 Youzhny 6-3, 7-6 (7-2) on the strength of four service breaks.
The first two breaks gave Kukushkin the first set but he needed both in the second set to force the tie-breaker. He took the advantage on the second point, winning off Youzhny's serve and consolidated that by taking another point from Youzhny to go up 5-2 and held serve from there for the match.
Youzhny fell to 7-10 in career ATP finals. He is 2-3 in title matches this year.
Kukushkin's first-place check of $113,600 nearly doubled his 2010 earnings total. Youzhny took home $59,900, which pushed him to more than $1.6 million for the year.