In an interview with Le Journal du Dimanche, Todt described the News of the World's allegations regarding Mosley's sexual activities as "regrettable and contemptible."
Mosley, who is suing the newspaper for unlimited damages, believes his private life has no relevance to his FIA position, and Todt agreed with this stance.
"For me, you judge somebody by the job he does," he said.
Todt said he could not understand why Mosley's critics were allowing the sexual allegations to overshadow his achievements at the FIA.
"He is a true president," said Todt, who has been tipped as a potential Mosley successor in some quarters.
"He knows his business very well because he is a hard-worker, thorough and reliable.
"He is very intelligent, and with a rare elegance.
"He knows how to impose leadership when he has to, with an international authority.
"He has worked very hard for safety.
"When you see what motor racing was like 30 years ago, especially on the circuits, what he has accomplished is remarkable.
"The number of lives saved under his aegis is absolutely phenomenal.
"He has taken some courageous decisions, sometimes against everyone, like the HANS device.
"Everyone was against that, but he was right.
"His work for road safety has brought a lot of progress.
"I'm therefore amazed to see that people are lingering on things which bear no relation to his position."
But while Todt said he hoped Mosley would be able to continue with his presidency, he admitted that the decision was solely in the hands of the FIA general assembly, which will hold a vote of confidence in him in an extraordinary meeting on 3 June.
"If you are asking me if I'm happy with the actions of the president of the FIA since he's been in office, I think he does a very good job," said Todt.
"Therefore I hope he will have the opportunity to carry on his work for several more years.
"But that said, we have to respect the rules of the FIA, which will meet on 3 June."