The study investigates how the presence of blockchain technology affects social fairness and selfish monetary decisions. Based on the assumption that blockchain technology enhances transparency and traceability in social exchanges, the study predicts that individuals will make less selfish decisions when blockchain is present. To test these predictions, the study conducted three experiments using a modified version of the dictator game scenario where participants decide how to divide a sum of money among themselves. In Study 1, the results show that individuals took less money for themselves and allocated more to the third player when blockchain technology was present, and the importance of social fairness was higher under the blockchain-presence condition. The mediation analysis indicates that the increase in social fairness mediates the effect of blockchain technology on monetary decisions. Study 2 replicated Study 1 with real monetary incentives. The results showed that individuals took less money for themselves only under the blockchain-image condition, and the importance of social fairness was higher only under the blockchain-image condition. Study 3 examined the moderating effect of the first player's allocation on participants' behavior under the presence or absence of blockchain technology. The study provides empirical evidence that blockchain technology can positively influence social fairness and reduce selfish monetary decisions. The findings have implications for policymakers and blockchain developers to design and implement blockchain systems that promote transparency and traceability in social exchanges, thereby enhancing social fairness.