Abstract: Abstract: Accelerating the formation of standards is the key for firms to win competitive opportunities. For example, Tesla has established a significant competitive advantage in the electric vehicle market by rapidly building a network of supercharging stations and formulating efficient charging standards; Kodak, once a giant in the photography industry, gradually lost its dominant position in the market because of its failure to launch digital photography standards in time. From various practical cases, we can see that taking the lead in launching standards has become an important way for firms to demonstrate their innovative strength, formulate technical rules and seize competitive opportunities in specific fields. In this regard, how firms can improve the efficiency of standardization and shorten the standard formation duration is a hot topic of concern for managers. Existing researches have richly studied the standard formation in the three aspects of firm resource capacity, external environment and standard alliance. Indeed, the research around the influencing factors of standard formation has made some progress, but there are still the following deficiencies that need to be further expanded. Firstly, the existing literature has mainly explored the impact of the size and membership diversity of standard alliance on standard formation from the perspective of individual firms, and lacks research at the alliance level. In fact, standard alliance is the main carrier to promote the process of standard development, and the power structure of alliance is the key factor affecting the operational efficiency of alliance. Secondly, the existing studies mainly take the number of standards developed by focal firms and the cumulative number of patent applications filed by the alliance as the proxy variables of standard formation, and lack the measurement of the efficiency of standard formation at the alliance level, so it is difficult to accurately answer the question of whether and how the standard alliance affects the efficiency of standard development. In summary, this paper focuses on further expanding the stream of literature along the level of standard alliance, and puts forward the research hypothesis on the power structure of standard alliance and the standard formation duration by using the transaction cost theory, and empirically tests the hypothesis by using 1,672 standard alliances in China's telecommunication industry from 2010 to 2020 as samples. The study finds that: the more decentralized the power structure of standard alliance, the longer the time needed to form the standard, because it limits the information processing efficiency and increases monitoring and coordination cost; the regional marketization gap enhances the positive effect of the power structure of alliance and the length of standard formation; the common partnership of alliance firms weakens the positive effect of the power structure of alliance and the length of technical standard formation. The heterogeneity analysis shows that progressive technical standard and standard alliance with younger members are more likely to be affected by the decentralized power structure of the standard alliance, and the positive effect of the decentralized power structure of the standard alliance on the length of technical standard formation is more significant. The relevant research findings provide theoretical support for firms to form standard alliance and accelerate the formation of standards.