The readiness of big data implementation in the East Java Provincial Government, especially in the regional government agency which has the main function as e-government public service agencies, is an important element in determining the success and sustainability of big data implementation within the East Java Provincial Government. Readiness analysis in public service organizations is needed to carry out their main tasks and functions in big data management and public services. This is needed so that the organization gets the maximum benefit from the use of big data analysis. This research discusses and analyzes the level of big data readiness in 5 regional government agencies in East Java using the gap analysis method based on in-depth interviews and data review. The results showed that in terms of big data implementation readiness, regional government agencies in East Java Provincial Government have not been able to implement big data optimally. In total, 66% of the organizations studied scored a readiness level of 3, while 33% of the organizations scored a readiness level of 2. Development in the aspects of IT governance, IT resources, internal attitude, external attitude, legal compliance, data governance, and human resources is needed because there is still a gap between the current condition and the expected ideal condition. This research also provides development proposals based on the Capability, Accessibility, Readiness, and Leverage (CARL) method for organizations to minimize gaps in order to improve organizational capabilities in Big Data implementation.