Eight years after competing in his last Olympics, Ndjissipou qualified for his third Central African team, as a 31-year-old, in the men's marathon at the 2004 Summer Olympics in Athens by receiving a berth from the IAAF World Championships in Paris. He finished the race with a forty-fourth place time in 2:21:23, trailing behind Italian runner and gold medalist Stefano Baldini and Brazil's Vanderlei de Lima (whose race had been grappled and pushed off by Irish protester Cornelius Horan) by an estimation of ten seconds. Building his own milestone as a three-time Olympian, Ndjissipou was appointed by the National Olympic Committee () to carry the Central African flag in the opening ceremony.