Robin van Persie's early goal seemed to have the Dutch nicely on course for a third successive win but they were hanging on somewhat after Samuel Eto'o equalised with a penalty on 65 minutes.
Robben then entered the fray 17 minutes from time for his first taste of tournament action after a hamstring strain and promptly thumped a 20-metre shot against the post.
It rebounded perfectly for fellow substitute Klaas-Jan Huntelaar to tuck in the 83rd-minute winner.
"It feels good to be back," Robben told reporters. "For me, this was an important moment.
"This is what I have been working for. It has been a long road and not a pleasant one."
Asked whether he was likely to be able to start the next match against Slovakia, Robben said: "You have to be realistic and honest to yourself. I know I can do better and that I am not fit yet."
Coach Bert van Marwijk was also delighted to have his most creative player available again. "I'm really pleased he played for 20 minutes and nothing happened (to the injury)," he said.
"I expect he can play longer at the next match but I'm not sure if he will start."
At one stage it looked as if Robben would not be needed as the Dutch enjoyed a spell of sharp-passing dominance after Van Persie shot the Dutch ahead.
However, they were forced to defend by a spirited Cameroon and neither Robben nor his coach were fully satisfied.
"Sometimes there was a lack of concentration in our passing," the winger said. "We can't make mistakes any more, we can't afford that against big teams in the knockout stage."
Van Marwijk added: "In the first half I was relaxed but in the second I thought Cameroon might score and we might even lose.
"Cameroon got a penalty and then we woke up... We won, yes, the first half was alright but the second was mediocre.
"This period of negligence is something we cannot afford. It might be because everyone was afraid of being booked. Nonetheless you saw these boys playing too carefully. Today was a lesson for the next match."
