The 22-year-old star from Ardglass, who has been prominent in stroke-play events in Scotland, Wales and Ireland this summer already became the first Irishman since Rory McIlroy (in 2006) to hold the famous trophy aloft.
Sharvin, who put himself in pole position with a stunning five under par 67 on Friday to take the lead, finished with a solid 70 for a 72-hole aggregate of seven under par 281.
And that total gave him a one-stroke victory over fellow Irishman and Walker Cup player Gavin Moynihan, the Dublin native who played out of The Island Club.
Sharvin carded four bogeys on the outward half and just one on the homeward stretch but seven pars to finish were sufficient for him to edge home.
Moynihan posted a brilliant concluding 66 which included two bogeys in the last three holes.An eagle three on the long sixth was the highlight of Moynihan’s last round.
In an excellent tournament for the Irish contingent, Jack Hume of Naas ended in joint third with the English pair of Charlie Danielson and Paul Kinnear, all carding totals of 284- four under par.
And Paul Dunne tied for ninth and Kevin Le Blanc and Dermot McElroy for 11th.
These performances will almost certainly cement places for Sharvin, Moynihan and Hume in the Great Britain and Ireland Walker Cup side to face the Americans at Royal Lytham and St Anne’s in September.