Lower Siang (Pron:/ˈsjæŋ or ˈsɪæŋ/) is one of the 25 administrative districts in the state of Arunachal Pradesh, India.

The creation of Lower Siang district was approved by the Arunachal Pradesh government of Nabam Tuki on 21 March 2013.

[3] The Government of Arunachal Pradesh approved creation of Lower Siang along with three other new districts in January 2013.

[5] On 22 September 2017 the commencement of operation of Lower Siang district, with Likabali as the temporary headquarters, was approved by the government led by Chief Minister Pema Khandu.

[8] The Lower Siang District is composed of Likabali and Nari-Koyu Assembly Constituencies.