Abstract: The Technical Guidelines for Cosmetics Safety Assessment (2021 Edition) (hereinafter referred to as Technical Guidelines) was issued by National Medical Products Administration, and came into effect on May 1, 2021. As a supporting document for the Regulations on the Supervision and Administration of Cosmetics, Technical Guidelines are used to standardize and guide the safety assessment of cosmetics. This article interprets the background, principles, and main contents of the Technical Guidelines, and discusses the possible impact on cosmetics regulatory departments, evaluation departments and manufacturers after implementation and countermeasures.