The British comedian, who was flanked by two women dressed in military uniforms, carried a golden urn decorated with the face of late North Korean dictator Kim Jong Il.
Cohen sprinkled ashes from the urn onto E! presenter Ryan Seacrest's tuxedo before emptying it onto the red carpet.
Moneyball star and 'Best Supporting Actor' nominee Jonah Hill said of Cohen's appearance: "I guess the Oscars isn't the best place to sell your movie. I think he's a funny guy, though."
The Bruno and Borat star reportedly faced opposition from the Academy Awards organisers after they disagreed with his plans to walk the red carpet as Aladeen.
Oscars producer Brian Grazer later insisted that Cohen was welcome to attend the awards as his latest comedy creation as they "respect him as an artist".
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Watch General Aladeen address his Oscars 'ban' below: