Kutai Kartanegara Regency (abbreviated as Kukar) is a regency of East Kalimantan Province, Indonesia. It has a land area of 27,263.10 km and a water area of 4,097 km, geographically located between 1°18′40″S and 116°31′36″E. The population of the regency was 626,286 at the 2010 Census and 729,382 at the 2020 Census; the official estimate as of mid-2023 was 788,113. The town of Tenggarong is the capital of the regency.

The regency includes the middle and lower reaches of the Mahakam River, the longest river in East Kalimantan, including its extensive delta. The city of Samarinda is situated on the river, about 48 km (30 miles) from its mouth; it is an administrative enclave within the regency, which thus contains much of the metropolitan area of Samarinda.

In 2019, President Joko Widodo proclaimed that the new national capital of Indonesia would be built in an area partly in the Kutai Kartanegara Regency and partly in the adjacent Penajam North Paser Regency and that the construction process would set off around 2024.

Kutai Kartanegara Regency lies in the historical region of Kutai, home to the first and oldest Hindu kingdom of Indonesia, the Kutai Martadipura Kingdom founded in the 4th century CE by King Kudungga.

From 1953 until 1960, the region became part of the Special Region of Kutai.

Kutai Kartanegara Regency is divided into twenty districts (kecamatan), tabulated below with their areas and their populations at the 2010 Census and 2020 Census, together with the official estimates as at mid-2023. The newly formed Kota Bangun Darat and West Samboja districts were split from Kota Bangun and Samboja districts respectively on 5 March 2021, but no separate figures are yet available for their areas, which are still included in the figures for the districts from which they were removed.

The table also includes the locations of the district administrative centres, the number of villages in each district (totaling 44 urban kelurahan and 193 rural desa), and its postcode(s).

Kode Wilayah	Name of District (kecamatan)	Area in km	Pop'n Census 2010	Pop'n Census 2020	Pop'n Estimate mid 2023	Admin centre	No. of villages	Post codes
64.02.13	Samboja	1,045.90	54,515	66,617	41,607	Kampung Lama	13	75271, 76276, 75277, 75279
64.02.20	West Samboja				31,513	Tani Bakti	10	75271 - 75274
64.02.14	Muara Jawa	754.50	33,923	41,561	44,070	Muara Jawa Ulu	8	75261 - 75267
64.02.15	Sanga-Sanga	233.40	17,588	19,728	20,969	Sanga-Sanga Dalam	5	75251 - 75256
64.02.03	Loa Janan	644.20	56,071	67,471	76,051	Loa Janan Ulu	8	75391
64.02.02	Loa Kulu	1,405.70	39,938	51,639	57,048	Loh Sumber	15	75571
64.02.01	Muara Muntai	928.60	17,315	19,396	21,234	Muara Muntai Ilir	13	75562
64.02.18	Muara Wis	1,108.16	8,557	9,398	9,730	Muara Wis	7	75559
64.02.08	Kota Bangun	1,143.74	31,292	36,655	23,839	Kota Bangun Ulu	11	75561
64.02.19	Kota Bangun Darat				14,468	Kedang Ipil	10	75561
64.02.06	Tenggarong	398.10	96,209	106,480	114,039	Melayu	14	75511 - 75517
64.02.07	Sebulu	859.50	36,420	40,925	43,329	Sebulu Ilir	14	75552
64.02.16	Tenggarong Seberang	437.00	61,441	67,877	73,060	Manunggal Jaya	18	75572
64.02.04	Anggana	1,798.80	32,688	33,416	38,674	Sungai Meriam	8	75381
64.02.05	Muara Badak	939.09	39,834	46,656	50,686	Muara Badak Ulu	13	75382
64.02.17	Marang Kayu	1,165.71	23,394	26,823	29,244	Sebuntal	11	75385
64.02.11	Muara Kaman	3,410.10	33,909	45,885	46,309	Muara Kaman Ulu	20	75553
64.02.09	Kenohan	1,302.20	9,861	11,588	12,346	Kahala	9	75564
64.02.10	Kembang Janggut	1,923.90	23,817	25,810	26,620	Kembang Janggut	11	75557
64.02.12	Tabang	7,764.50	9,908	11,457	13,277	Sidomulyo	19	75558
	Totals	27,263.10	626,286	729,382	788,113	Tenggarong	237

Notes: (a) Samboja District comprising 10 urban kelurahan (Handil Baru, Handil Baru Darat, Kampung Lama, Muara Sembilang, Samboja Kuala, Sanipah, Sungai Seluang, Tanjung Harapan, Teluk Pemedas and Wonotirto) and 3 rural desa; the new Samboja Barat District comprises 9 urban kelurahan (Amborawang Darat, Amborawang Laut, Argosari, Bukit Merdeka, Karya Merdeka, Margomulyo, Salok Api Darat, Salok Api Laut and Sungai Merdaka) and 1 rural desa.
(b) included in the figures for Samboja District, from which it was split off in 2021. (c) including 14 offshore islands.
(d) all 8 are kelurahan (Dondang, Muara Jawa Pesisir, Muara Jawa Ilir, Muara Jawa Tengah, Muara Jawa Ulu, Muara Kembang, Tama Pole and Teluk Dalam).
(e) all 5 are kelurahan (Jawa, Pendingin, Sanga-Sanga Dalam, Sanga-Sanga Muara and Sarijaya). (f) including one offshore island.
(g) included in the figures for Kota Bangun District, from which it was split off in 2021.
(h) including the offshore island of Pulau Kumala. (i) comprising 12 urban kelurahan (Baru, Bukit Biru, Jahab, Loa Ipuh, Loa Ipuh Darat, Loa Tebu, Maluhu, Mangkurawang, Melayu, Panji, Sukarame and Timbau) and 2 rural desa. (j) including the offshore island of Pulau Yupa.
(k) including 32 offshore islands, and mainly comprising the extensive delta of the Mahakam River.
(l) except the desa of Sidomulyo, which has a postcode of 76131. (m) including 6 offshore islands.

Bukit Bangkirai (Bangkirai Hill) is a 1,500-hectare natural tropical located about 58 kilometres (around 45 minutes by car) from the city of Balikpapan. Plants of the family Dipterocarpaceae dominate in the area, especially Bangkirai trees (Shorea laevis of the genus Shorea) growing to 40–50 metres in height. There are over 120 bird species as well as gibbons (Müller's Bornean gibbon), macaque monkeys (Southern pig-tailed macaques, Crab-eating macaques), Maroon leaf monkeys, Banded pigs, and Banggai crows. Black Orchids (Coelogyne pandurata), among 45 kinds of orchids, are endemic to Bukit Bangkirai.

To visit the forest, visitors can walk along a 64-metre canopy bridge that connects five big Bangkirai trees 30 metres above the ground.

In 2011, East Kalimantan province developed an 18-hectare plot of land for mangrove information and research center in Sepatin village, in Anggana District, as Bali has done. It will function as a research, exhibition, information, breeding as well as education center on mangroves, especially in the Mahakam Delta.

In early 2015 it was announced that part of Kutai Kartanegara Regency had been selected to be a trial 'smart city', the first in Indonesia, based on the Fujisawa Sustainable Smart Town (SST) concept. The aim of the SST concept was to reduce CO₂ emissions by 70 percent and reduce consumption of water by 30 percent. The Kutai Kartanegara area was chosen as a trial area because of good investment growth in the region, the extensive area, relatively moderate levels of population density, effective planning in the area, and rich energy resources.

• Kutai, (historical region in eastern Borneo)
• Kutainese language
• Legend of the Centipede Lake

• Official website