(Reuters) "We have formalised our candidacy after financial problems were resolved last night," FIDAL spokesman Maco Sicari said.
FIDAL said Rome city council and regional authorities had pledged a total of EUR17million ($14.77m) to cover the cost of hosting the event.
The final decision is expected to be taken at a meeting of the International Association of Athletics Federations (IAAF) on April 14 in the Kenyan capital Nairobi.
"We believe in our bid," Sicari added. "We have a great tradition of organising world-class sporting events and the public here loves them."
The cities of Berlin, Munich, Stuttgart, Brussels, Budapest, Moscow and Helsinki are also potential candidates to host the games, according to the IAAF.
The bidding process had to be reopened after original hosts London withdrew when the British government in October shelved a plan to build a stadium for the event.
The world athletics championships are the biggest tournament in the world after the Olympics and soccer's World Cup.
Rome has made a formal bid to host the World Athletics Championships in 2005, the third-biggest sporting event in the world, Italy's Athletics Federation FIDAL has confirmed.
