In order to improve the reliability of distribution grid, it achieves automatic fault isolation and restoration of power supply by controlling the line switches in distribution automation system. However, the topology of the distribution grid is complex. The change of distribution load and operating mode after line reconstruction makes the protection settings of the line need adjusting accordingly, which cannot be solved by traditional tie switches. This paper designs a work mechanism of adaptive protection setting adjustment based on data-driven idea by using smart tie switch. As the intelligent center of the line, smart tie switch uses the tele-metering and tele-signaling data acquired from section switches to compute protection settings by using the proposed mechanism, which can realize automatic matching of switch protection settings and distribution load & operating mode after line reconstruction. The effectiveness and applicability of the method are verified by example analysis and engineering project. This work is supported by National Natural Science Foundation of China (No. 61473050) and Science and Technology Project of State Grid Corporation of China (No. PD71-15-049).