A liquid level sensing apparatus (10) for long-distance automatically enhancing a signal-to-noise ratio is applied to a measured target (20). The liquid level sensing apparatus (10) includes a sensing module (102), a long-distance command receiving module (104) and at least a brake module (106). The sensing module (102) transmits a sensing signal (108) to the measured target (20). The sensing signal (108) touches the measured target (20) to reflect back a reflected signal (110). The sensing module (102) receives the reflected signal (110) to measure the signal-to-noise ratio and to measure a height of the measured target (20). The long-distance command receiving module (104) is electrically connected to the sensing module (102). The long-distance command receiving module (104) receives a long-distance command signal (302). The brake module (106) is mechanically connected to the sensing module (102).