Prem Chandra Gupta is a close aide of RJD supremo Lalu Prasad.
The RJD announced its candidates for two Rajya Sabha seats in Bihar on Thursday, rebuffing ally Congress, which had been demanding one of the seats.
At a press meet, Rashtriya Janata Dal (RJD) state president Jagadanand Singh announced the names of Prem Chandra Gupta and Amarendra Dhari Singh for two of the five seats that will go to polls.
The opposition camp is expected to wrest the two seats from the ruling NDA.
Mr Gupta, a close aide of RJD supremo Lalu Prasad, is currently a member of the Upper House of Parliament from neighbouring Jharkhand, but his term expires next month. Gupta had served as a cabinet minister in the UPA-1 government.
Mr Singh is a well-known entrepreneur based in Patna and his candidature, which has taken many by surprise, is being seen as an attempt by the RJD to win over the upper castes ahead of the Bihar Assembly polls due later this year.