The win was their fourth straight.
Trevor Van Riemsdyk, Evgeni Kuznetsov, Marcus Johansson, Lars Eller and Alex Ovechkin scored for Washington.
Dimitri Orlov had a pair of assists for the Capitals.
Charlie Lindgren stopped 29 shots for Washington, who moved to 14-12-4.
Adam Lowry and Pierre-Luc Dubois replied for Winnipeg.
Connor Hellebuyck made 31 saves for the Jets, who dropped to 18-8-1 and saw their four-game winning streak snapped.
There was no scoring in the first period.
Trevor Van Riemsdyk got Washington on the board 3:25 into the second when Jim Dowd hit him with a short pass at the top of the face off circle before the Capital defenceman moved into the high slot before beating Hellebuyck high glove side.
The goal was his 2nd of the season.
Evgeni Kuznetsov gave the Capitals a two-goal cushion 8:21 into the second period on the power play when John Carlson found him alone in front of the net and drifted a pass through.
Kuznetsov buried a backhand, beating Hellebuyck high glove side to make it 2-0 Capitals.
“They tell us that they (Jets) have a good goalie and we have to go screen him. I saw that Johnny got the puck and probably both guys go over to the big man and I just went to open up the back door and then Johnny just passed it through,” said Kuznetsov.
Marcus Johansson scored shorthanded on a penalty shot at 9:55 after being fouled from behind by Jets defenceman Josh Morrissey.
Johansson moved in and beat Hellebuyck with a backhand shot just under the cross bar.
The goal was his 7th of the season.
Lars Eller made it 4-0 when he scooped up a rebound off a Anthony Mantha shot from the slot into a wide open net at 15:24.
The veteran forward was playing in his 900th NHL career game.
"We got contributions from a lot of places and Charlie was so strong in net. Just you one of these sixty minute efforts where you know it was only those first five minutes in the third where they (Jets) pushed and were able to get two quick ones. After that I just think we responded really well. And you know didn't panic and kept them from getting too chances after that. So it was a really overall good game tonight," said Eller.
Adam Lowry got the Jets on the board, firing a rebound off a Josh Morrissey shot from the left point 35 seconds into the third.
The goal was his 7th of the season.
Pierre-Luc Dubois scored at 3:39, converting a cross-ice feed as Kyle Connor hit him with a searing pass.
Dubois hammered the puck past Lindgren to make it 4-2.
"We didn’t give up. Down 4-0, we kept going and kept pushing," said Dubois. "Their goalie played well. We hit some posts and had some chances at the end of the second period. It could have been a two or three goal game instead of a four goal game going into the third. And who knows what happens after that? Now we have a huge game against a Western Conference team, so we’re going to have to be ready for that. They’re a good team.”
Alex Ovechkin added an empty netter at 17:48 to seal the win for Washington.
The goal was his 17th of the season.
Jets Head Coach Rick Bowness said his club came out flat.
"We didn’t have our legs early, that was clear. They were jumping on us. I thought as the first period went on we got our legs going again. Clearly the coverage on their first goal was a complete breakdown for us. Power play hurt us, you get a four-minute and give up the breakaway and the penalty shot, it kind of sets you on your heels a little bit against a veteran hockey club. They know how to play. I liked how we finished the second period, the last four minutes. We felt we were still in the game, and we were. We made it 4-2 and we just didn’t get that third goal. We started trading chances, but that’s the only way you’re going to get back in the game. Give them credit, they bent a little bit but didn’t break. We had some really good looks at the end of the second. We hit the post. We had some really good looks. Their goalie made some timely saves for them," he said.
Washington visits Chicago Tuesday while Winnipeg hosts Vegas.
SHOTS-WASHINGTON 36 WINNIPEG 31