Big Data is becoming a new asset in the agri-food sector including enterprise data from operational systems, sensor data, farm equipment data, etc. Recently, Big Data applications are being implemented, aiming at improving farm and chain performance. Many companies are refraining from sharing data because of the fear of governance issues such as data security, privacy and liability. Moreover, they are often in a deadlock or afraid to take the first step even though they expect to develop new business with data. To accelerate the development of Big Data applications, this paper analyses governance issues and introduces a set of guidelines for governance of data sharing in agri-food networks. A framework for analysis was derived from literature and used to identify lessons learned from recent projects or initiatives. From these results, a set of draft guidelines was developed. The framework and guidelines were evaluated in a workshop. The framework consists of factors that are related to governance on data sharing in networks. Internal factors are: efficiency, effectiveness, inclusiveness, legitimacy & accountability, credibility and transparency. External factors are: political, economic, social, technological, legal and environmental factors. For each of these factors, guidelines are provided in terms of: issues to be addressed, best practices and lessons learned from other projects and initiatives. It is concluded that the framework is complete in covering all relevant issues on governance in data sharing but the guidelines must be considered as a first set, which can be further improved and extended in the future. A wiki-type-of-website could help to upscale the guidelines at a global level. The guidelines could also be further refined accounting for different maturity levels of agri-food networks. The guidelines in this paper are considered to be a valuable step into the direction of solving governance issues in data sharing, which is expected to accelerate Big Data applications in the agri-food domain.