Exhibit 99.1

Joint Filing Agreement

In accordance with Rule 13d-1(k) promulgated under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with all other Reporting Persons (as such term is defined in the Schedule 13G referred to below) on behalf of each of them of a statement on Schedule 13G (including amendments thereto) with respect to the Class A ordinary shares, par value of US$0.00001 per share, of Yatsen Holding Limited, a Cayman Islands exempted company, and that this Agreement may be included as an exhibit to such joint filing. This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned hereby execute this Agreement as of February 3, 2021.

Zhen Partners Fund IV, L.P.	By: By:	Zhen Partners Management (MTGP) IV, L.P. its General Partner Zhen Partners Management (TTGP) IV, Ltd. its General Partner
	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory
Zhen Partners Management (MTGP) IV, L.P.	By:	Zhen Partners Management (TTGP) IV, Ltd. its General Partner
	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory
Zhen Partners Management (TTGP) IV, Ltd.	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory
Zhen Fund COV LLC
	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory

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Zhen Advisors Ltd.	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory
Zhen International Ltd	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory
Rosy Glow Holdings Limited	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory
Best Belief PTC Limited	By:	/s/ Xu Xiaoping
	Name:	Xu Xiaoping
	Title:	Authorized Signatory
Xu Xiaoping		/s/ Xu Xiaoping

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