Document And Entity Information - shares	9 Months Ended
	Mar. 31, 2026	May 12, 2026
Document Information Line Items
Entity Central Index Key	0001892316
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Fiscal Year Focus	2026
Document Transition Report	false
Entity File Number	0-56615
Entity Registrant Name	LONGDUODUO COMPANY LIMITED
Entity Incorporation, State or Country Code	NV
Entity Tax Identification Number	37-2018431
Entity Address, Address Line One	G3-5-8016 Shui’an Town
Entity Address, Address Line Two	Ruyi Headquarters Base
Entity Address, Address Line Three	Hohhot Economic Development Zone
Entity Address, City or Town	Inner Mongolia
Entity Address, Postal Zip Code	010000
Entity Address, Country	CN
City Area Code	+86
Local Phone Number	(0472) 510 4980
Title of 12(b) Security	None
No Trading Symbol Flag	true
Security Exchange Name	NONE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		30,015,036
Amendment Flag	false
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--06-30