The Red Shirts fell 19-0 behind early on as Cornish Pirates scrum-half Will Riglesford, Freddie Elliott and Ben Chambers all crossed, Jake Hanley with two conversions.
Army replied with Jack Johnson on target following Matt Dawson’s try, but Navy skipper Jarrad Hayler and Hanley struck back.
Their opponents, though, grabbed the final points of the first half as prop Sitiveni Vasuturaga grabbed a seven-pointer.
And the comeback continued after the break with ex-Newcastle Falcon Vereimi Qorowale further recuing the deficit.
Hanley slotted a penalty, but Pete then burst free and dived over for a three-point game at 29-26.
Yet his opposite man, Fijian international Sam Matavesi, gave Navy breathing space with Hanley converting his try.
The Red Shirts reply was swift, however, and they were level as Tomasi Vula and Jack Johnson crossed within a minute of one another.
But it was the men in blue who landed the decisive blow, Jack Wright mauling over in the 77th minute.
A name well-known as a Rams’ opponent, Taunton Titans back row Ratu Vakalutukali, was named man-of-the-match.
Victory ensured Royal Navy are back-to-back Inter-Services champions for the first time in 52 years.
They had previously beaten Royal Air Force 47-16.
Speaking to BFBS Sport, Pete admitted: “We’re all very privileged to play in front of so many lovely people in this amazing stadium.
“The first 10 minutes we couldn’t get a grip of the game and from there we were chasing it.
“In the last 10 I thought we might have sneaked a try, but it didn’t come our way.”
British Army take on Royal Air Force at Gloucester’s Kingsholm Stadium on Saturday, May 16 (3.15pm).
*Pictures by Alligin Photography
