Tachakittiranan made her first Thai team, as a 17-year-old teen, at the 2000 Summer Olympics in Sydney. There, she failed to advance into the succeeding round in any of her individual events, finishing forty-fifth in the 50 m freestyle (27.31), thirtieth in the 200 m freestyle (2:05.88), and thirty-ninth each in the 100 m freestyle (58.69) and 400 m freestyle (4:29.28).