The two were rushed to Pushpanjli hospital, where doctors declared her dead. The condition of Sharma remains critical.
The body of Darwesh Yadav has been sent for post mortem, a police officer said.
Darwesh Yadav was elected president of the Bar on June 9 at Prayagraj. She was the first woman president of the Bar Council.
Manish Sharma was her close associate. The two were meeting lawyers in their chambers to thank them for their support.
Some eye witnesses said the two had heated arguments in senior lawyer Arvind Mishra's chamber, when Manish Sharma lost his cool, pulled out his pistol and fired at Darwesh from point blank range.