<p>A testing finger (1) comprises a finger-shaped rod (2). A sharp end (3) of the finger-shaped rod (2) is connected with a testing part used for measuring a distance. The testing part is a group of testing heads, and the length of each testing head corresponds to minimum safe distances at different voltage levels in intrusion protection. The testing part is connected with the sharp end (3) of the finger-shaped rod (2) in a detachable insertion manner. The testing finger (1) can accurately determine whether the distance between a live part or a live lead which is not insulated in an electrical device and a protective part is greater than or equal to a minimum safety distance, thereby solving the problem in the prior art that the distance between the sharp end (3) of the finger-shaped rod (2) and the live part or the live lead cannot be accurately measured by a clamp in a situation of limited space.</p>
