The incident took place on Saturday when the 46-year-old Ramesh Mishra was on his way back home from Khamaria town where he runs a medical store, they said.
Mishra was riding pillion on a bike when the bike-borne assailants shot at him. A doctor riding the bike rushed him to the district hospital from where he was referred to the Lucknow Trauma Centre in a serious condition.
"An FIR has been lodged and police teams have been formed to identify the attackers and the motive behind the attack," ASP Shailendra Lal said.
Police have detained two suspects for interrogation.
Describing the attack on the journalist as a "serious" matter, local journalists called on police authorities and demanded speedy investigation and arrest of culprits.