The Frenchman capitalised on a mix-up in the QPR defence to put the Magpies 2-1 up after 35 minutes at Loftus Road on Sunday.
The score would remain the same until the final whistle, with the precious three points lifting Newcastle up to 13th in the table and ensuring they will be playing top-flight football next campaign.
It was Gouffran's third goal for the North-East club since signing from Bordeaux in the January transfer window and arguably his most important.
The 26-year-old acknowledges the significance of the result and believes the club can now look to the future with optimism.
"This is so important for the players, the manager and of course our brilliant fans," he told the Chronicle. "Of course I was happy to score, especially as it won the game and the result was so important to the club. It was a good moment
"The players have worked very hard to win this match. They were strong and worked hard to get the points. We're happy to win the game. I think they deserved it.
"After the game everybody was happy. Now we need to finish the game season well against Arsenal.
"Then we can really start looking towards next year. This is so important to the club."