[Purpose/significance] With the rise of encrypted digital currencies and new distributed community computing paradigms based on blockchain technology such as Bitcoin, Ethereum and etc, more and more traditional Internet project can use Blockchain's chained data structure, decentralized network, and security mechanism to reshape the data production, which is conducive to improving the overall utility of the system. This paper aims to use Blockchain technology to empower online social media platforms and build a trusted community ecology with clear economic incentives. [Method/process] Quantifying the value contribution of platform users through bottom-up cluster voting based on the users’ speech power, and then an incentive mechanism for platform content producers and content evaluators was designed to motivate content producers to post high-quality real content and content evaluators to actively participate in content evaluation, and it could also suppress evaluators from colluding to vote and encourage evaluators to vote critically. [Result/conclusion] Through numerical analysis and simulation, we verified the effectiveness of the designed incentive mechanism. Finally, we implemented the designed online social media platform based on Ethereum.