Klizan made the most of his opponent's nervous start to break immediately. The 41st-ranked Slovak then saved four break points in the fourth game and built a 5-1 lead.
Gimeno-Traver, who played in his first final, dropped his serve in the third game of the second set and Klizan went up 5-2. He fended off three other break points to serve out the match.
Klizan's previous titles came in St. Petersburg in 2012 and Munich last season.