The development of big data and artificial intelligence has profoundly influenced the social life of human beings, changed our production and life style and led to a number of challenges for the law. We are moving from the internet society to the algorithmic society, with algorithms intervening in the overall private law field including contracts, torts, corporate governance, insurance contracts, and securities transactions in different forms and latitudes. In the algorithmic society of artificial intelligence, the group of algorithmic consumers formed. The premise for discussing how algorithms affect the effectiveness of legal acts is whether they affect person's intention manifestation. Algorithms are series of digital program logic constructed on the basis of natural language. Algorithms have a certain degree of learning ability, which can learn continuously and deeply through big data. However, it is neither learning in cognitive level nor human learning. The essence of algorithms is a kind of procedural Marble Maze Game based on Boolean algebra, which does not conform to the structure of intention manifestation in civil law. The intention manifestation made by the algorithmic system of automated decision-making is still an extension of human intention manifestation. Algorithm users form algorithm power based on big data and algorithm divide, which will affect the system of intention manifestation. Algorithm will not pose a fundamental challenge to the effectiveness system of legal acts, but it needs to be reinterpreted in the specific constitutive elements of mistake and fraud. When it comes to interpretation, a distinction needs to be made between different scenes where the user of algorithms is the actor or his counterpart in discussion. In the algorithmic society, consumers evolve to a new type of consumers: algorithmic consumers. In response to the inadequate algorithmic consumer protection in the existing private law framework, the mode of truly disclosure obligation in the Insurance Law should be adjusted, and the Consumer Law should reshape the rights and obligations between operators and consumers. In commercial and financial field, financial institutions using algorithms will have a higher duty of care. Multi-dimensional factors should be considered in algorithmic consumer protection. On the one hand, it is necessary to build a personal information protection system and take information fiduciary duty as corporate social responsibility. On the other hand, we should build the algorithmic transparency system, algorithmic audit system, algorithmic ethics and other comprehensive supervision systems to regulate algorithm. The essence of regulating algorithms through laws and rules is to regulate how algorithmic users (such as algorithmic businesses or platforms) use algorithms regularly and reasonably in the process of online transactions or operations. The present research on artificial intelligence should return to academic rationality and avoid blindly following the trend of fantastic jurisprudence. The core and key of algorithmic consumer protection in the algorithmic era lies in how to strike a balance between personal information protection, algorithm regulation and algorithmic enterprise development.