Sintang Regency is a regency of West Kalimantan province of Indonesia. It covers an area of 21,638.2 km, and had a population of 364,759 at the 2010 Census and 421,306 at the 2020 Census; the official estimate as at mid 2023 was 438,022 (comprising 226,018 males and 212,004 females).

Sintang Regency is one of the few Indonesian regencies having a land border with another country (in this case, with Malaysia). It is also the third largest regency in the province by land area after Kapuas Hulu Regency and Ketapang Regency. The regency was formerly the site of the Sintang Kingdom, a Hindu kingdom that later converted to Islam and which was a regional power in the interior of Borneo Island. The regency seat is located at the large town of Sintang, which is among the biggest settlements in Borneo's interior alongside Putussibau and Puruk Cahu.

Somewhere between 45,000 and 39,000 B.C. the Sintang area was first inhabited by humans. The area changed hands several times from the Majapahit to the Bruneian Sultanate, but when the Dutch arrived at Borneo in 1776 the area was quickly occupied by the Dutch

The area was occupied by the Empire of Japan in 1941 as a result of WW2, and then was liberated in 1945. This was followed by Indonesian Independence.

Sintang, the seat of the regency has a tropical rainforest climate (Af) with heavy to very heavy rainfall year-round.

Following the separation of the former southern part (eleven districts) to form the separate Melawi Regency on 18 December 2003, the residual Sintang Regency consists of fourteen districts (kecamatan), tabulated below with their areas and their populations at the 2010 Census and 2020 Census, together with their official estimates as at mid 2023. The table also includes the locations of the district administrative centres, the number of administrative villages in each district (totalling 390 rural desa and 16 urban kelurahan - the latter all in Sintang District), and its post code.

Kode Wilayah	Name of District (kecamatan)	Area in km	Pop'n 2010 Census	Pop'n 2020 Census	Pop'n mid 2023 Estimate	Admin centre	No. of villages	Post code
61.05.14	Serawai	2,261.37	21,922	22,771	22,935	Nanga Serawai	38	78683
61.05.15	Ambalau	5,991.97	12,867	13,259	13,324	Nanga Kemangai	33	78684
61.05.09	Kayan Hulu	1,790.01	21,854	22,758	22,939	Nanga Tebidah	31	78694
61.05.03	Sepauk	1,502.71	46,407	53,251	55,208	Nanga Sepauk	39	78662
61.05.02	Tempunak	873.89	26,860	30,163	31,076	Nanga Tempunak	26	78661
61.05.20	Sungai Tebelian	597.64	29,144	34,679	36,334	Sungai Ukoi	26	78655
61.05.01	Sintang	355.65	59,410	77,319	83,144	Sintang (town)	29	78611 - 78619
61.05.07	Dedai	599.53	27,573	30,127	30,793	Penyak Lalang (Nanga Dedai)	31	78691
61.05.08	Kayan Hilir	1,050.46	24,423	27,562	28,437	Nanga Mau	43	78693
61.05.19	Kelam Permai	642.11	15,276	18,433	19,391	Kebong	17	78656
61.05.21	Binjai Hulu	377.48	11,332	13,910	14,706	Binjai Hulu	11	78663
61.05.04	Ketungau Hilir	1,630.88	20,567	24,100	25,138	Nanga Ketungau	24	78652
61.05.05	Katungau Tengah (Central Ketungau)	1,970.41	27,421	30,413	31,221	Nanga Merakai	29	78653
61.05.06	Ketungau Hulu	1,993.89	19,703	22,561	23,376	Senaning	29	78654
	Totals	21,638.20	364,759	421,306	438,022	Sintang	406

Note: (a) comprising 16 urban kelurahan (Akcaya, Alai, Batu Lalau, Kapuas Kanan Hilir, Kapuas Kanan Hulu, Kapuas Kiri Hilir, Kapuas Kiri Hulu, Kedabang, Ladang, Mekar Jaya, Mengkurai, Menyumbung Tengah, Rawa Mambok, Sengkuang, Tanjung Puri and Ulak Jaya) and 13 desa.

There are 193 kindergartens, 456 elementary schools, 142 junior high schools, and 44 senior high schools. In addition, there are 18 vocational high schools. The regency has a total of 10 universities and higher education institutions as of 2020, most of which are located in the town of Sintang. One of the most notable in the regency is Kapuas Sintang University, located in Sintang district. The university is private and located close to the Kapuas River. It was previously known as Panca Bhakti Teaching and Education College before becoming a university. Muhammadiyah University in Pontianak also has a campus branch in Sintang, which is also private. Other colleges in the regency include Christian theological schools such as Sintang Khatulistiwa Theological College, Injili Setia Sintang Theological College, Kapuas Raya Christian College, and Immanuel Sintang Kalbar Theological College. In addition, there is a public academy owned by the West Kalimantan provincial government and one private Islamic college, Ma'arif Sintang Islamic College.

The regency government also runs a regional library, located in the town of Sintang.

0°04′05″N 111°29′53″E / 0.06806°N 111.49806°E / 0.06806; 111.49806