Behind the superb Rojas, Shanieka Ricketts, Jamaica, finished second in 14.89, which she jumped in the first round.
American Tori Franklin won the bronze at home.
The Venezuelan Rojas, who improved her own world record to 15.74 in March this year, is the first woman to win three World Cup gold medals in three steps.
She herself has set the goal of jumping over the dream limit of 16 meters, but failed to do so in the last jump in the final.
- I came here with the goal of being closer to my world record.
The wind affected my approach.
I tried to adjust, but the most important thing was to win the gold medal and be consistent over 15 meters.