A tie rod is a steel rod used in construction to hold, secure, or resist tension in structural or formwork elements. In shuttering and formwork, tie rods are placed through wall, column, or beam formwork panels to hold the opposite panels together, preventing them from spreading outward under the pressure of fresh concrete. They are usually made of mild steel and fitted with nuts and washers at both ends, which are tightened to secure the panels.

Tie rods transfer the lateral pressure of wet concrete safely to the opposite side or to external support members, ensuring that the formwork remains aligned, stable, and does not bulge. After the concrete sets, the rods are typically removed or cut off, leaving the structure intact.