The 6ft 7in marksman, on loan from Aston Villa, followed up his first goal for the Canaries against Burnley with the winner to help Norwich complete their first away win of the season at Priestfield Stadium.
Norwich boss Nigel Worthington has invested in Crouch, Darren Huckerby and Kevin Harper in an effort to boost his squad for another tilt at the Premiership and all three were involved in the goal that decided the game.
Huckerby and Harper set it up for Crouch to bundle the ball home, only to earn a booking for over-celebrating with the delighted Norwich fans at the Town End.
It was one of six yellow cards brandished by Premiership referee Graham Barber, making a rare excursion into the Nationwide League.
He went for his card as early as the 11th minute to punish John Hills for flooring Harper. Gills player-manager Andy Hessenthaler and Nyron Nosworthy were also booked while Clint Easton and Harper both earned yellows for heavy challenges on Danny Spiller.
Norwich were recently linked with interest in Marlon King and the 23-year-old striker missed a great chance to put the Gills ahead as early as the fifth minute.
Spiller did some great work in the box, but King missed badly sending his free header wide of the upright.
Huckerby's pace was a constant threat as Norwich won three quick corners and they took the lead with a fine volley from Damien Francis just before the half hour.
The former Wimbledon midfielder caught the eye throughout and unleashed a 20-yard plus volley that flew past Jason Brown.
Twelve minutes Gillingham got back on level terms. Rod Wallace set it up and King fired home from around 12 yards for his second goal in successive home games.
Crouch's winner was the only shot Norwich had on target in the second half while Norwich keeper Robert Green kept his side in front with a fine save to deny Paul Shaw.
Gillingham missed a great chance to snatch a point late on when Shaw crossed for Mark Saunders to head narrowly over from six yards out.
Gillingham: Brown, Nosworthy, Cox, Hope, Hills, Spiller, Hessenthaler, Saunders, Shaw, King, Wallace. Subs: Smith, Ashby, Tommy Johnson, Bossu, Perpetuini.
Yellow Cards:
J.Hills, 10, unsporting behaviour
A.Hessenthaler, 20, dissent
N.Nosworthy, 82, unsporting behaviour
Norwich: Green, Edworthy, Mackay, Fleming, Drury, Harper, Francis, Holt, Easton, Crouch, Huckerby. Subs: Mulryne, Roberts, Crichton, Notman, McVeigh.
Yellow Cards:
C.Easton, 30, unsporting behaviour
K.Harper, 63, unsporting behaviour
P.Crouch, 68, unsporting behaviour
Referee: Graham Barber (Hertfordshire)
Attendance: 8,022