The Irishman, playing through the pain barrier with a hernia problem that will require surgery at some point - most likely in the next international break - sent Jussi Jaaskelainen the wrong way from the penalty spot on 13 minutes to claim his fourth goal of a stand-out campaign thus far.
It was a controversial decision from Kevin Friend, who penalised Joey O’Brien for a perceived push on Brady which looked a soft award, akin to the one which saw the Tigers again the beneficiaries in the home game against Norwich on August 24.
O’Brien was displeased and so was his manager Sam Allardyce, with salt rubbed into their wounds with Brady, who netted from 12 yards in the decisive moment against the Canaries at the KC, tucking the ball home effortlessly again.
Allardyce was also increduous in the second half when Friend rebuffed huge appeals for a spot-kick when Jake Livermore appeared to handle, but the Leicestershire officials waved away the protests fifteen minutes from time.
That said, Friend afforded the Londoners a let off early on when Hammers skipper Kevin Nolan was only cautioned for a two-footed and reckless challenge on Liam Rosenior, which could - and should - have brought a red card.
For sheer collective commitment alone, Hull merited victory with their defensive resolve outstanding and try as they might, the Hammers - whose travel sickness continued with their run without a goal extending to 360 minutes - six hours - couldn’t unlock the door.
For Hull, a solid start to their top-flight adventure has now turned into a very good one, with Tigers having now moved up to seventh spot, above Manchester United no less.
After Brady’s opener, both sides had their chances in an entertaining first-half, with Matt Jarvis sending Modibo Maiga clear after a poor pass from Ahmed Elmohamady, only for Allan McGregor to get his angles right and clutch the striker’s low shot.
City then survived a major scare on 23 minutes when a header from James Tomkins following Matt Jarvis’ corner was cleared on the goalline by the chest of Elmohamady, with TV replays showing that the whole of the ball had not crossed the line.
A fresh-air shot from Mohamed Diame then spurned another good chance for the visitors before Mark Noble, who spent an undistinguished and short-lived spell on loan at Hull earlier in this career, firing a fierce effort wide.
Hull responded strongly with two set-piece opportunities within the space of sixty captivating seconds somehow ending without a second home goal.
Both chances came from Brady corners, with the first met by Curtis Davies, whose goalbound header was diverted by Maiga onto the top of the bar and over and from the next flag-kick, Elmohamady’s header was brilliantly beaten away by Jaaskelainen.
Sone Aluko, eye-catching again, saw an effort rightly ruled out for offside early in the second half before McGregor palmed away a well-struck 20-yarder from Diame.
The Hammers enjoyed plenty of territory in the opening to the second half, with Hull content to soak things up and hit the visitors on the break, with the next chance arriving at the feet of a man badly in need of a goal in Danny Graham, who fired over at the far post after Brady’s free-kick wasn’t cleared and found its way to him.
Midway through the half, the hosts were within centimetres of a relieving second goal as the visitors pressed with Graham teeing up Jake Livermore, whose thumping low drive smashed against the post with Jaaskelainen beaten.
In the main, it was a story of West Ham pressure, but the hosts refused to buckle and cleared their lines magnificently, with the likes of Davies and Figueroa working overtime, although some leniency from Friend appeared to deny the visitors a penalty with Livermore made a movement towards a cross with his arm, with the ball deflected for a corner.
A rare home slip then briefly let in Razvan Rat on the left, but he failed to show composure and blazed over - beating the turf in obvious frustration.
The Hammers continued to lay siege and threw bodies forward in the final ten minutes, but Hull steadfastly held firm, with the visitors only sniff seeing Vaz Te connect with an overhead kick with McGregor comfortably saved.
Hull City: McGregor, Rosenior, Faye, Davies, Figueroa, Elmohamady, Huddlestone, Livermore, Brady (Meyler 80); Graham (Sagbo 70), Aluko (Boyd 88). Unused substitutes: Harper, Bruce, McShane, Quinn.
West Ham: Jaaskelainen; O’Brien, Tomkins, Reid, Rat; Diame (Downing 70), Morrison, Noble, Jarvis (Vaz Te 70); Nolan, Maiga (Petric 59). Unused substitutes: Adrian, Taylor, Collins, Demel.
Attendance: 24,291 - 2,337 West Ham fans.
Referee: G Friend (Leicestershire).