The Newcastle United striker, on a half-season loan at the promotion-chasing club, netted in last night's 2-0 win over Leeds United at Craven Cottage.
Mitrovic scored with a precise low shot seconds after Caleb Ekuban spurned a chance at the other end of the pitch.
Fulham manager Slavisa Jokanovic said: "Mitrovic's good player – he's made a great job for us.
"I repeat many times, he's an important signing for us. He scored another goal and worked in the offensive and defensive set-pieces.
"He can hold the ball. What's important is we start our striker and he scores the goals. He made his job, and I expect he will go in similar level to push hard like he is right now."
Fulham, in third place, are now five points behind second-placed Cardiff City, and Jokanovic still believes his team can clinch an automatic promotion place.
"It depends on them (Cardiff)," said Jokanovic. "We can do it. We can try and repair ourselves and be ready for our next game. It's our ambition to fight for three points every week. But everything depends on Cardiff – they must lose.
"They have five points and that is a big difference. We will try and do our job. It's a race. We will try and chase.
"We must try to push harder and try and win the next game. They need to have some mistakes to give us the opportunity."
Mitrovic, a Serbia international, left Newcastle in January in search of regular first-team football ahead of the summer's World Cup finals.