India winning the toss and batting first amassed 304-3 to which Sri Lanka could reply with only 160 in 38.4 overs.
The Lankan batting was dismantled by slow left-arm orthodox bowler Harsh Tyagi who ended up with figures of 6 for 38 in 10 overs.
Opener Nishan Madushanka (49) and Navod Paranavithana (48) were the main scorers for Sri Lanka.
In the Indian innings openers Yashasvi Jaiswal (85) and Anuj Rawat (57) put together a first wicket stand of 121 to set India towards a match winning total.
Skipper Simran Singh and Ayush Badoni also contributed with half-centuries.
Scores: India (U19) 304-3 in 50 overs (Y Jaiswal 85, A Rawat 57, D Padikkal 31, Simran Singh 65 n.o., A Badoni 52 n.o.)
Sri Lanka (U19) 160 in 38.4 overs (Nishan Madushanka 49, Pasindu Sooriyabandara 31, Navod Paranavithana 48, S Desai 2/37, H Tyagi 6/38)