West Champaran (Hindi: पश्चिम चंपारण ज़िला, Urdu: مغرِبی چمپارن ضلع Maġribī Čaṃpāraṇ Zilā) is an administrative district in the state of Bihar in India. It is a part of Tirhut Division. The district headquarters are located at Bettiah.

It is known for its porous border with Nepal, as well as the high levels of crime and smuggling that accompany this. It was the main transit point for Ganja and Weapons travelling between India and Nepal, however the new government in Bihar has led to a significant reduction in kidnapping and smuggling in the area. It is currently a part of the Red Corridor.

West Champaran district occupies an area of 5,228 square kilometres (2,019 sq mi), comparatively equivalent to Canada's Amund Ringnes Island.

West Champaran District was carved out of the old Champaran District in the year 1972 as a result of re-organization of the District in the state. It was formerly a subdivision of Saran District and then Champaran District with its Head quarters as Bettiah. It is said that Bettiah got its name from Baint (Cane) plants commonly found in this district. The name Champaran is a degenerate form of Champaka aranya, a name which dates back to the time when the district was a tract of the forest of Champa (Magnolia) trees & was the abode of solitary asectics.

Champaran is a historic region around 26°50′37″N 84°40′57″E / 26.8437°N 84.6826°E / 26.8437; 84.6826Coordinates: 26°50′37″N 84°40′57″E / 26.8437°N 84.6826°E / 26.8437; 84.6826, which now forms the East Champaran district, and the West Champaran district in Bihar. Champaran was part of erstwhile Bettiah Raj. Bettiah Raj's eighteen hundred square miles yielding a rental of almost 2 million rupees made it the second largest zamindari in Bihar belonging to a Bhumihar Brahmin family.

Champaran District was created in 1866. On 1 December 1971 it was split into two districts: Paschim Champaran and Purbi Champaran. The headquarter of Paschim Champaran district is at Bettiah. The headquarters of Purbi Champaran district is at Motihari. Purbi Champaran consists of six subdivisions and twentyseven blocks. Nepal forms its northern boundary, Sitamadhi and Sheohar are to the east while Muzaffarpur lies to the south and with part of Gopalganj bounds it on the west.

The name Champaran derives from Champa-aranya or . Champa or champaka means magnolia and aranya means forest. Hence, Champaranya means forest of magnolia trees. It is believed that the forest was named while its western portion was inhabited by solitary ascetics.

Mohan Kumar (June 1, 1934 in Sialkot) is an Indian film director, producer and screenwriter, who worked in the Bollywood (Hindi) film industry of India born in undivided India who after Partition moved to India and settled down in Bombay.