贝特蒂亚（Bettiah），是印度比哈尔邦Pashchim Champaran县的一个城镇。总人口116692（2001年）。

该地2001年总人口116692人，其中男性61803人，女性54889人；0—6岁人口19265人，其中男10033人，女9232人；识字率64.51%，其中男性为70.74%，女性为57.50%。

Bettiah (Bɛtɪjɑː,Bɛtɪjɑː) is a city and the administrative headquarters of the West Champaran district (Tirhut Division) - (Tirhut), near Indo-Nepal border, 225 kilometres north-west of Patna, in Bihar. It was the seat of the majestic Bettiah Raj, established in the 17th century. Its palaces and temples narrate its magnificent history. It has a Roman Catholic Mission, which was established in 1740 and the municipality, established in 1869. It came on the rail-map of the country, as early as 1883 and witnessed the first experiment with non-violence by Mahatma Gandhi in India during his Struggle for the Abolition of Indigo Plantation in 1917. It is an agricultural trade centre and has several industries, like, sugar, leather, brass, besides food processing centres.