At the 2004 Summer Olympics in Athens, Wu swam only in two events with one day in between. He posted FINA B-standard entry times of 52.03 (100 m freestyle) and 2:08.12 (200 m individual medley) from the National University Games in Taipei. On the fifth day of the Games, Wu placed fifty-fourth in the 100 m freestyle. He edged out Singapore's Mark Chay to take a seventh spot in heat three by a quarter of a second (0.25) in 52.58. The following day, Wu managed to repeat a forty-fourth-place effort in the 200 m individual medley. Swimming in heat two, Wu saved a sixth spot over Turkey's Orel Oral by 0.12 of a second in 2:08.72.