A novel trust-based range-free secure algorithm using blockchain technology is considered in hostile WSNs for localization. The trust values of beacon nodes are evaluated against reputation value, mobility, residual energy and neighbor node list. The blockchain technology is implemented then to share the beacon nodes trust value with neighbor nodes. The highly trustworthy beacon nodes are subsequently elected as a miner for the mining process of blocks so that unknown nodes get information from highly honest beacon nodes to perform the localization process correctly. A set of simulations is conducted to validate the effectiveness of the proposed algorithm compared to the existing one.