Stanmore booked their place in the Shepherd Neame South-East Finals after wrapping up the Middlesex Twenty20 final at the Common on Monday.
They beat defending champions Finchley by 13 runs in the final having despatched Ealing in the semi final earlier in the day. The shield was presented to them by former Middlesex and England star, Angus Fraser.
Batting first, Stanmore got off to a flier with openers Nick Goh and Omar Anwar putting on 58 runs in the first six overs. Zawar Hussain (25) also pitched in as Stanmore posted 120 for five in their allocated overs.
In reply, the Finchley batsmen struggled on a slow wicket and failed to make headway against Stanmore's slow bowling attack of Marc Reingold, Goh and Mukesh Bhatt. Left arm seam bowler, Paul McIvor, took three for 25 with skipper Reingold claiming three for 17. Jake Milton top scored for Finchley with 38 but it was not enough as they crashed to 107 all out.
Earlier, Goh was the star of the semi final as Stanmore beat Ealing by seven wickets in the semi final. He took four for nine in four overs to help reduce Ealing to 120 for seven before enjoying an innings of 18. Stanmore were steered home by Alistair Fraser (42*) and Reingold (19*).
Stanmore now play the winners of the other Shepherd Neame leagues, Essex, Kent and Surrey, at the County Ground, Canterbury on September 14.
The overall winner goes through to the televised national finals at Cardiff's Millennium Stadium later that month.
