Fourth-seeded Rahul surpassed compatriot Karan Rajan Rajarajan 21-15 21-13 in the summit clash to lay claim to the title at the Molade Okoya-Thomas Hall of the Teslim Balogun Stadium on Saturday.
The 19-year-old, who had won the Maritius Open last year, stunned top-seed and World No. 55 Misha Zilberman in the semifinals.
A shuttler from Gopi Chand Academy, Rahul had recently won the bronze medal in the Russain Open Grand Prix.
In women's singles, India's Mugdho Agrey finished as runners-up after losing 12-21 14-21 to Sri Lanka's Thilini Pramodika Hendahewa in the finals.