It is reported that open data (OD) leads to transparency, citizen participation, cooperation, growth of the economy and public service. The open data ecosystem is described as a network of interactions between stakeholders involved in data processing, application development, privacy protection, security, and usage. The paper's main objective is to examine Croatia's open data ecosystem, where following sub-objectives are proposed: (i) to define a level of the OD ecosystem of Croatia that will be analyzed; (ii) to determine the most developed OD portal based on number of published datasets (iii); to analyze the current state of a selected OD portal.