Raghunathpur is located in the Siwan district of Bihar. The current MLA from this constituency is Harishankar Yadav of Janata Dal (United) (JDU) who bagged 61,757 votes in the 2020 elections. He beat his closest rival Manoj Kumar Singh Lok Janshakti Party (LJP) by a margin of 17,965 votes.

In the 2015 elections, the total number of registered electors were 265,711. Out of these, 141,182 electors were male, 124,519 were female and 10 electors belonged to the third gender. Voter turnout in this election was 54.78% as 145,562 electors out of the total registered electors cast their ballots.

In the last legislative assembly elections in 2020, the Election Commission put the total number of registered electors at 296,780. Out of these, 152,283 electors were male, 144,488 female and 9 were of the third gender in this constituency. Voter turnout in this election was 59.55% as 158,931 electors cast their votes.

According to the 2024 Election Commission data, the Raghunathpur constituency has a total of 308,263 registered voters — 157,722 male, 150,530 female, and 11 third gender electors. Polling for the constituency was held in the first phase of elections on November 6, 2025.

Raghunathpur is a very important town through which many pilgrims pass to reach Baba Brahmeshwar Nath Temple and the town itself has many significant temples. This constituency covers an approximate land area of 253.97 square kilometers and its geographic coordinates are 26° 07 '35.0"N 84° 08' 53.5"E. Raghunathpur shares its borders with five other legislative assembly constituencies, including Siwan, Barharia, Daraundha, Darauli and Ziradei.