Telecommunications itself has a very important role for society in interacting and as a means of exchanging information, facilitating financial services, and so on. Legal protection for consumers who use cellular telecommunications services is of course to provide good service to consumers, thereby creating responsibility for business actors. The existence of problems regarding SMS spam which is detrimental to consumers invites attention to immediately resolve the problem. There is one case, namely Alvin Lie as a consumer who received spam SMS from PT Indosat Tbk. which is felt to have disturbed the comfort of a consumer. Alvin Lie has submitted complaints and complaints regarding the spam SMS he received but did not receive clarity, so he filed a lawsuit in court as a way to obtain legal certainty and protection. The research method used is normative legal research. Legal protection against spam SMS received by Alvin Lie from PT Indosat Tbk. divided into 2 (two), namely: preventive consumer legal protection and repressive legal protection. In the case studied, repressive legal protection is more reflected, marked by the filing of a lawsuit at the Central Jakarta District Court with case number 464/Pdt.G/2020/PN.Jkt.Pst. Responsibility of cellular operator companies for consumer losses due to sending spam SMS in the case of Alvin Lie with PT Indosat Tbk. included as a principle of responsibility based on fault, because there are indications that PT Indosat Tbk. has been negligent in managing PT Indosat Tbk's services. which results in sending spam SMS.