Rhys McClenaghan produced a personal best score of 15.450 to take gold on the pommel horse at the World Challenge Cup in Slovenia.
The 2018 European and Commonwealth champion finished comfortably ahead of Ilyas Azizov, who scored 13,950 to finish second.
Great Britain’s Jamie Lewis finished fourth with compatriot Adam Tobin in sixth.
McClenaghan returned to action in May having recovered from shoulder surgery.
The Newtownards native missed April’s European Championships having undergone an operation on his shoulder in November.
His victory in Slovenia continues an impressive run of form for the 19-year-old, who also won silver in China last month.
Ciaran Gallagher, CEO Gymnastics Ireland, said: “Following on from his fantastic silver in China this gold is further evidence that Rhys is back to top form after his surgery last year.
“It bodes very well for his preparations as we go into the World Championships in Stuttgart in October, one of the primary Tokyo 2020 Olympic qualification events.