Kapilvastu is a constituency of the Uttar Pradesh Legislative Assembly covering the city of Kapilvastu in the Siddharthnagar district of Uttar Pradesh, India.

Kapilvastu is one of five assembly constituencies in the Domariyaganj Lok Sabha constituency. Since 2008, this assembly constituency is numbered 303 amongst 403 constituencies.

Members of the Legislative Assembly

From	Term	Name	Party
2012	16th Vidhan Sabha	Vijay Kumar	Samajwadi Party
2017	17th Vidhan Sabha	Shyam Dhani	Bhartiya Janata Party
2022	18th Vidhan Sabha	Shyam Dhani	Bhartiya Janata Party

Election results

2022

2022 General Elections: Kapilvastu

Party		Candidate	Votes	%	±%
	BJP	Shyam Dhani	122,940	48.72
	SP	Vijay Kumar	92,001	36.46
	BSP	Kanhaiya Prasad	26,662	10.57
	Sabka Dal United	Bhaggan	2,698	1.07
	INC	Devendra Singh Guddu	2,484	0.98
	NOTA	None of the Above	2,279	0.90
Majority			30,939	12.26
Turnout			252,356
	BJP hold		Swing

2017

Bharatiya Janta Party candidate Shyam Dhani won in last Assembly election of 2017 Uttar Pradesh Legislative Elections defeating Samajwadi Party candidate Vijay Kumar by a margin of 38,154 votes.

2017 General Elections: Kapilvastu (SC)

Party		Candidate	Votes	%	±%
	BJP	Shyam Dhani	1,14,082	49.07	27.26
	SP	Vijay Kumar	75,928	24.31	16.88
	BSP	Chandra Bhan	37,166	15.98	0.95
	NOTA	None Of The Above	2,623	1.13	1.13
		Remainder 3 candidates	5,330	2.27
Majority			38,154	16.23	3.16
Turnout			2,35,172	54.61	5.04
	BJP gain from SP		Swing	0.65

16th Vidhan Sabha: 2012 General Elections

2012 General Elections: Kapilvastu (SC)

Party		Candidate	Votes	%	±%
	SP	Vijay Kumar	78,344	41.19	41.19
	BJP	Sri Ram Chauhan	41,474	21.81	21.81
	BSP	Patturam Azad	32,204	16.93	16.93
	INC	Kailash Prasad	11,554	6.07	6.07
	Independent	Manju Devi	8,776	4.61	4.61
	Independent	Anil Kumar	4,479	2.35	2.35
	PECP	Motilal Vidyarthi	3,510	1.85	1.85
	Independent	Shiv Dayal	1.895	1.00	1.00
		Remainder 8 candidates	7,960	4.19
Majority			36,870	19.39	19.39
Turnout			1,90,196	49.56
	SP win (new seat)