In the digital economy, data plays an increasingly important role, but the dominant undertaking with large amounts of data often deny other undertakings’ access to data with the intention of monopolizing data resources. It is necessary for the competition law to regulate the refusal of data access by the dominate undertaking through essential facility doctrine, so as to realize data access and promote the circulation and utilization of data resources. Combined with the development history of essential facility doctrine, the application of essential facility doctrine in the context of the digital economy requires strict conditions. These conditions include: under the precondition that the undertaking has a dominant market position, firstly, data needs to constitute an essential facility which means that data is indispensable for undertakings to participate in market competition; secondly, the negative effect of the dominant undertaking’s refusal of data access is obviously greater than the positive effect; finally, there is no reasonable reason for the dominant undertaking’s refusal of data access. It is only after the above conditions are met that the dominant undertaking needs to be under an obligation to allow data access. On this basis, the competition law needs to refine the specific requirements for data access and its possible relationship with the personal data protection law and intellectual property law to make data access more operational in practice. Specifically, there are three main competition law requirements for data access: first, other undertakings’ access to the data should be fair; second, other undertakings’ access to the data should be realistically practicable; and third, other undertakings’ access to the data is subject to the payment of a reasonable fee. In terms of the relationship between competition law and personal data protection law, on the one hand, personal data protection law hinders to a certain extent the access to data by other undertakings; on the other hand, there is a unity of value between personal data protection law and competition law. In terms of the relationship between competition law and intellectual property law, in most cases, it is legitimate for a dominant undertaking to deny other undertakings’ access to data protected by intellectual property rights, but the dominant undertaking also needs to be careful to exercise its rights within reasonable bounds and not to abuse its intellectual property rights to restrict data access. In the era of digital economy, it is necessary for China to incorporate essential facility doctrine into the normative system of antitrust law, and at the same time, design the specific content of data access in relevant legal norms and guidelines, and strengthen the coordination with the protection of personal data, intellectual property rights and other relevant legal norms, so as to realize the localized construction of data access, promote market competition, and explore the great value of data.