Provided are a thin film transistor sensor and a manufacturing method thereof. The thin film transistor sensor includes a first substrate and a second substrate opposite to each other, the first substrate includes a first flexible base substrate and a first gate electrode disposed on the first flexible base substrate, and the second substrate includes a second flexible base substrate and a second gate electrode disposed on the second flexible base substrate; the second gate electrode is at least partially overlapped with and separated from the first gate electrode, and configured to be electrically connected to the first gate electrode after the thin film transistor sensor is applied with a voltage, such that the thin film transistor sensor is turned on.