Singh, accompanied by a small group of his supporters, filed his nomination papers at the district collectorate here, his media in-charge Brijesh Mahaur said.
Three of his rival candidates -- Chaudhri Babulal of BJP, Pakshalika Singh of SP and Seema Upadhyay of BSP -- also filed their nominations from the seat.
Singh, a former confidant of SP chief Mulayam Singh Yadav, was expelled from the party in 2010. He joined the Ajit Singh-led RLD, an ally of Congress, last month along with Rampur MP Jaya Prada.
Meanwhile, a case has been filed against BSP candidate for Agra Lok Sabha seat Narayan Singh for violation of the Model Code of Conduct, additional district magistrate P P Pal said.