The district covers an area of 2,426 km2 (937 sq mi) and had a population of 392,604 in 2001 and 420,477 in 2011.

The district renamed as Makwanpur on the name of Makwanpurgadhi and the headquarter moved to Hetauda in 1982.

At the time of the 2011 Nepal census, Makwanpur District had a population of 420,477.

As their first language, 45.8% spoke Tamang, 41.5% Nepali, 4.1% Newari, 3.9% Chepang, 1.4% Magar, 0.9% Bhojpuri, 0.6% Maithili, 0.5% Rai, 0.2% Gurung, 0.2% Lepcha, 0.2% Majhi, 0.1% Hindi, 0.1% Pahari, 0.1% Tharu, 0.1% Urdu and 0.2% other languages.

[6] Ethnicity/caste: 48.3% were Tamang, 14.1% Hill Brahmin, 10.5% Chhetri, 6.2% Newar, 4.6% Chepang/Praja, 4.5% Magar, 2.9% Kami, 1.9% Rai, 0.8% Damai/Dholi, 0.8% Majhi, 0.7% Gurung, 0.4% Musalman, 0.4% Thakuri, 0.3% Danuwar, 0.3% Kathabaniyan, 0.3% Pahari, 0.3% Sanyasi/Dasnami, 0.3% Sarki, 0.2% Gharti/Bhujel, 0.2% Tharu, 0.1% Terai Brahmin, 0.1% other Dalit, 0.1% Ghale, 0.1% Hajam/Thakur, 0.1% Kalwar, 0.1% Kanu, 0.1% Limbu, 0.1% Marwadi, 0.1% Sunuwar, 0.1% Teli, 0.1% other Terai, 0.1% Yadav and 0.2% others.