A spring probe includes a needle, a spring sleeve sleeved onto the needle, and a protrusion. The spring sleeve has upper and lower non-spring sections, and at least a spring section therebetween. The needle has a bottom end portion protruding out from the lower non-spring section, and a top end portion located in the upper non-spring section. The protrusion is located at one of the top end portion and the upper non-spring section. The needle is movable relative to the upper non-spring section from an initial position to a connected position where the upper non-spring section is electrically connected with the needle through the protrusion when receiving an external force. As a result, the spring probe effectively prevents signals from being transmitted through the spring section, thereby improving stability of signal transmission and preventing the spring section from fracture.