The number of data created is rapidly growing. Through the large number of the data, online social network brings strong impact on the data sharing on today’s generation. Centralized organization like Google, Facebook, Amazon, etc. take a big part to provide service to store the data and the platform to share the data using their cloud system. However, privacy and security become main issue in term of data sharing. In centralized system, data owners have no control over their own data when the data has been shared. Once the data owner share and provided rights to a third parties or centralized organizations to access the data, the data owner no longer guarantees that the data will be safeguarded. The main cause of the problems is the data access problem.
Utilized by the blockchain systems, the data sharing can be secure and private. By removing the need for a trusted third parties and enables the automated control of the personal data. The data owners are able to share their personal data and have full control over their data and get transparency over the users who access the data. In addition, distributed file system used to store large data to reduce the cost to store the data in the blockchain.
In this work, a blockchain-based access control mechanism is designed and implemented using Ethereum and to ensure the privacy of data sharing. The mechanism proposed to get secure and private data sharing between each user and get transparency over the users who access the data while maintaining the cost of the data storage.

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