With the advancement of time, the production of cosmetic products in Indonesia has been increasing every year. This is also supported by the rapid growth of consumers using cosmetics. The implication of the growth of cosmetic producers and consumers is the deviation in the language of cosmetic advertisements circulating in Indonesia, especially by influencers. Advertisements created by businesses are naturally aimed at expanding market reach and increasing the product's sales value. However, in some cases, businesses resort to unethical methods to achieve these goals. One such method is presenting advertisements containing exaggerated promises about the benefits and uses of a product, which seem to meet consumer needs, even though, in reality, the product does not provide the benefits as promised in the ad. This research aims to examine the implementation of Law No. 8 of 1999 on Consumer Protection in relation to violations of cosmetic advertising ethics by influencers, as well as analyze the accountability of cosmetic producers in cases of ethical violations in social media advertisements. The research method used in this study is normative legal research, with an approach to legislation and a case law approach in Indonesia. The analysis of violations of cosmetic advertising ethics by influencers is conducted in accordance with the Consumer Protection Law (UUPK), with findings indicating that the existing regulations are still ineffective in addressing violations in the advertising sector due to a legal gap in Indonesia's advertising industry. Furthermore, there are two possible ways to demand civil accountability from advertising businesses: through a breach of contract lawsuit arising from contractual relationships, and a lawsuit for unlawful acts by applying the principles of product liability or professional liability.