Jonathan Dwyer added 107 yards rushing in his second NFL start. Pittsburgh jumped on Washington (3-5) early, scoring on its first four possessions and never letting Griffin get loose.
Heath Miller caught four passes for 46 yards and his sixth touchdown of the season for the Steelers, who suddenly look like their normal selves in a wide-open AFC.
Playing in 1934 throwback uniforms that made certain players resemble hulking bumblebees, Pittsburgh improved to 14-1 against rookie quarterbacks since 2004, doing to Griffin what they've done to the likes of Eli Manning and Joe Flacco.
The second overall pick in last April's draft has taken the NFL by storm, his dazzling playmaking turning the moribund Redskins into one of the league's more compelling teams.
It all came to a crashing halt on a wet, raw day at Heinz Field. Washington receivers struggled to catch the ball dropping 10 passes and Griffin found little room to showcase his brilliant speed. He ran just five times and was hemmed in by a defense that looked just fine without safety Troy Polamalu.
The Steelers held the NFL's top rushing offense to a season-low 86 yards and made sure Griffin got knocked around whenever he attempted to freelance.
Washington did its best to free up space for Griffin, at one point sending him out as a wide receiver in the second quarter. But Griffin was flagged for pass interference while trying to grab Josh Morgan's wobbly pass, another mistake by the Redskins on an afternoon full of them
While Washington looked very much like a work in progress, the Steelers continued to round into form.
Pittsburgh wobbled to a 2-3 start that included losses to Oakland and Tennessee, raising questions about the Steelers' ability to contender.
Not so fast.
Roethlisberger continued to thrive in new offensive coordinator Todd Haley's system, spreading 24 completions to nine receivers. Dwyer, starting in place of injured Rashard Mendenhall, became the first Steelers running back to top 100 yards in consecutive games in four years.
Pittsburgh wasted little time putting the pressure on. Roethlisberger marched the Steelers 76 yards on 12 plays to start the game, the final play a 1-yard touchdown pass to little-used tight end Leonard Pope.
The Steelers made it 10-0 on a 48-yard field goal by Shaun Suisham, but the Redskins got back in it briefly when Griffin connected with Santana Moss for a 2-yard score on fourth-and-goal. The extra point was blocked, however.
Pittsburgh, which reached Washington territory on its first six possessions, went in front 17-6 when Roethlisberger ad-libbed in the pocket and found Miller in the back of the end zone.
The score was Miller's 37th career scoring grab, tying him with Elbie Nickel for the franchise record for touchdown receptions by a tight end. Suisham added a second field goal late in the half.
The Steelers made a habit the first few weeks of the season of failing to put away opponents. They had no trouble Sunday. After Kai Forbath's field goal pulled Washington within 20-9, Roethlisberger directed Pittsburgh 80 yards in 11 plays, pushing the lead to 27-9 on a 1-yard flip to fullback Will Johnson.
Washington mustered little the rest of the way and eventually lost its composure. Cornerback DeAngelo Hall was ejected in the fourth quarter after getting in the face of an official., and Griffin ended the day with a simple kneel down on the Redskins' last possession, eager to get out of the rain and away from the worst performance of his short career.
Washington 12, Pittsburgh 27
Washington 0 6 3 3 12
Pittsburgh 10 10 7 0 27
Pit • Pope 1 pass from Roethlisberger (Suisham kick), 7:55.
Pit • FG Suisham 48, 2:49.
Was • Moss 2 pass from Griffin III (kick blocked), 11:33.
Pit • Miller 7 pass from Roethlisberger (Suisham kick), 6:17.
Pit • FG Suisham 27, 1:56.
Was • FG Forbath 48, 11:52.
Pit • W.Johnson 1 pass from Roethlisberger (Suisham kick), 5:13.
Was • FG Forbath 45, 12:06.
Attendance • 62,371.
First downs 17 25
Total Net Yards 255 355
Rushes-yards 21-86 27-140
Passing 169 215
Punt Returns 2-34 3-25
Kickoff Returns 4-97 3-51
Interceptions Ret. 0-0 0-0
Comp-Att-Int 16-35-0 24-33-0
Sacked-Yards Lost 1-8 1-7
Punts 4-37.8 3-50.7
Fumbles-Lost 1-0 0-0
Penalties-yards 7-55 3-20
Time of Possession 26:47 33:13
Rushing • Washington, Morris 13-59, Young 1-10, Morgan 1-9, Griffin III 6-8. Pittsburgh, Dwyer 17-107, Rainey 4-26, Roethlisberger 2-6, B.Batch 4-1.
Passing • Washington, Griffin III 16-34-0-177, Morgan 0-1-0-0. Pittsburgh, Roethlisberger 24-33-0-222.
Receiving • Washington, Morgan 5-46, Paulsen 4-43, Moss 4-21, Paul 1-37, Hankerson 1-16, Briscoe 1-14. Pittsburgh, Wallace 7-62, Miller 4-46, A.Brown 4-38, Sanders 3-56, W.Johnson 2-8, B.Batch 1-8, Dwyer 1-8, Pope 1-1, Rainey 1-(minus 5).
Missed Field Goals • None.