In the era of digital economy, against the backdrop of cities’ transformation toward smartization, the issue of government-market relations has extended to new dimensions in the field of urban governance. Specifically, private technology enterprises, by virtue of their products and services, can influence public decision-making, impact or even challenge public values, and even exacerbate existing inequalities, as well as barriers to access to opportunities and resources, thereby undermining high-quality development and the interests of the public.This article first analyzes the reasons and rationale for the widespread adoption of public-private partnership (PPP) in smart city construction, i.e. there is a natural correlation between smart cities and PPP based on the similarity of historical origins, commonality of concepts, and the unique advantages of the PPP model in smart city construction. On this basis, it explores possible sources of risk to public values in the PPP model, such as data privacy, multi-actor collaboration and risk-sharing, political commitment, equality of opportunity, and technology and regulation, focusing on the issues of vendor lock-in and embedding of technology values that are different from those of traditional infrastructure construction, but rather are closely related to smart city technologies. The article shows how PPP and smart cities are shaping for-profit companies into central players in the creation of efficient and innovative public services and infrastructure. Current data protection legislation, including the EU’s GDPR, is still insufficient to provide pragmatic guidance on maintaining the two core public values of accountability and transparency. Data legislation has problems in protecting public values in terms of where control resides, as well as how to provide a basis for legal data processing and establish relevant accountability systems on this basis. Based on the various barriers and limitations of the smart city PPP model, this paper points out that there is a need to introduce a broader concept of openness to extend public norms to private actors (technology firms) acting or serving public goals, and publicizing them through contractual agreements, so that the two core public values of transparency and accountability are transmitted to private technology firms and enterprises in smart city projects, and to mitigate the risks of smart technologies being divorced from public scrutiny and people being passively marginalized. The novelty of this paper lies in its novel discussion of the possibilities and limitations of utilizing PPP in smart cities as a tool for safeguarding public values, pointing out that PPP poses a serious challenge to the core principles of accountability and transparency of public governance. In light of the unique complexities of distributing and transferring benefits and rights in PPP smart city projects, this paper explores whether and how publicizing can be an alternative to extending public value to private partners, and makes an attempt to expand the realm of government-market relations in digital urban governance.