Mr Nishant Patel, who went missing from his hotel in Hardoi district on Monday, was found near Lucknow Buddheshwar crossing in an unconscious state.
The Congress leader was found unconscious with head injuries.
He has been admitted to a local hospital.
Mr Nishant Patel, a close aide of Mr Rahul Gandhi, is the son of senior Gujarat Congress leader and former minister Hasmukh Patel. He was in Hardoi since the past one fortnight to oversee the Youth Congress elections.
Nishant left his room in Utsav Hotel on Monday morning went missing. His mobile phone and suitcase were found in the hotel room when some Youth Congress leaders came to the hotel to Mr Nishant Patel and found the door open.
The hotel security guard said that Nishant had left the hotel around 5 am on Monday and had boarded an autorickshaw. Mr Nishant Patel had spoken to his father on phone on Sunday night and sounded normal.
Meanwhile, police officials said that they were waiting for the Congress leader to regain consciousness so that they could question him and initiate further action if necessary.