Maharajganj Lok Sabha constituency (Hindi: महाराजगंज लोक सभा निर्वाचन क्षेत्र) is one of the 40 Lok Sabha (parliamentary) constituencies in Bihar state in eastern India.
Presently, Maharajganj Lok Sabha constituency comprises the following six Vidhan Sabha (legislative assembly) segments. This includes 4 assembly segments of Saran district.