The 24-year-old man was left in a critical condition when he was shot during an incident in Reginald Street, Chapeltown, at 7.15pm.
Officers including armed police attended the scene to investigate and the National Police Air Service helicopter was also drafted in.
Detective Superintendent Jim Dunkerley, of the Homicide and Major Enquiry Team, said: “This is clearly a very serious incident and a full investigation is underway this morning into the firearms discharge on Reginald Street.
“The 24-year-old victim received life threatening injuries as a result of what took place and is being treated in hospital this morning.
“There may well have been people around in the area at the time the incident occurred and I would urge anyone who saw would took place to contact us.”
Patrols are continuing in the area today as enquiries continue into events surrounding the shooting.
Superintendent Warren Stevenson, of Leeds District Police, said the the incident had naturally caused concern in the community.
"We are investigating what has happened and our increased patrols in the area are continuing to provide a reassuring presence," he said.
“I would urge anyone who has information about what happened to get in contact so we can bring those responsible to justice.”
Anyone with information is urged to call police via 101, quoting log 1730 of August 1.