The 38-year-old Frenchman's triumph at the wheel of a Mitsubishi Pajero/Montero Evolution marked a fourth successive win for the Japanese manufacturer and a record-breaking ninth overall victory for the Pont-de-Vaux-based MMSP factory team.
Peterhansel also became only the second individual in Dakar history to win the world's most famous endurance rally on a bike and in a car (Hubert Auriol won two bike titles and the 1992 Paris to Cape Town Rally for the Mitsubishi team).
Stephane's success came 12 months after the six-times motorcycle winner's victory aspirations had ended in bitter disappointment when he threw away a potential win on the penultimate stage and was forced to settle for third overall.
"On the liaison section this morning I couldn't help but think about last year", said a delighted Peterhansel. "It has been a long time to wait one year for this victory. There were many times when it was easy to make a mistake. I spoke with Jean-Paul when we crossed the finish line of the special today and thanked him for a great job. I am happy for him. It's his first Dakar win.
For the first win with the bike I had to wait four years. For the first win with the car it took me six. It is a completely different feeling. Hiroshi drove a perfect race as well, but it was my turn this time!"
Defending champion and team mate Hiroshi Masuoka, partnered by Gilles Picard, finished runner-up in the second of the Mitsubishi Pajero/Montero Evolutions, 49m 24s behind Peterhansel. The Japanese former leader had shadowed his team mate since losing more than an hour with a transmission problem on the Atar to Tidjikja stage in Mauritania last week.
"I am very pleased for Stephane and for Mitsubishi", said Masuoka. "I drove a good race. It was not easy. Mauritania was difficult. Next year I will push for the third win."
Co-driver Gilles Picard was delighted with his second position. "I am happy to be here" said Picard. "It has been a great team performance. I just wish sometimes that the media would not just highlight the role of the co-driver when we make a small mistake. I know that we are here to be in the shadow of the driver, but it is never easy to finish the Dakar."
MMSP's German support crew Andrea Mayer and Andreas Schulz completed the 11,052 kms route in an excellent fifth overall in their Mitsubishi Pajero/Montero. The success was Mayer's first Dakar as a member of the full Mitsubishi factory team acting as a support driver for Peterhansel, Masuoka and Italian Miki Biasion.
"It is a different feeling to finish this race as a member of an official team", said Mayer. "On a bike you are alone. When I crossed the finish line today I knew it had been a great team effort. Andreas has been fantastic. I know he is used to challenging for the win, but he has been crucial to my result. I know I still have things to learn, but Andy, the mechanics and all the team have supported me to Dakar and I thank them with this fifth place."
Peterhansel and Masuoka had dominated the Dakar Rally since the event entered Morocco and the traditional African special stages. Peterhansel eventually finished 3h 00m 33s ahead of Jean-Louis Schlesser's third-placed Buggy, his nearest non-Mitsubishi rival. Stephane won two of the timed competitive sections, Masuoka won four.
The Italian duo of Miki Biasion and Tiziano Siviero were forced to retire the team's fourth car after rolling on the Ouarzazate to Tan-Tan stage in Morocco.
"It was a great victory and the whole team worked very hard for it", said MMSP's Head of Motorsport Sven Quandt. "I am happy that we made it one, two and five. I think it was fair for Stephane to win this time. He deserves to be very happy and proud of himself today. Andrea had a very good result, perhaps better than we expected. She drove in a very professional manner. It was one of the toughest Dakars that I have seen, which is good for Mitsubishi because we have shown that we can win the hardest of all the rallies."
"My feeling is strange", said MMSP's Team Director Dominique Serieys. "Everybody in the team has done a good job. We could not win this rally if the tip of the iceberg was not functioning and the mechanics and drivers of the trucks can be proud of themselves. It may have looked easy from the outside, but we had our fair share of problems to overcome.
This is a great win for Mitsubishi, but it is also a human win - a great day for Stephane. It was the same when Hiroshi lost in 2001 and he won the following year. It has been a long 12 months for Stephane. I feel really emotional as well for Jean-Paul and Andrea. She drove a great rally. She was always smiling and never complaining."