A multi-tier limit-angle protection device, adapted to detect a rotation angle about a rotation axis of a driving apparatus to thereby control operation of a driving motor of the driving apparatus, the multi-tier limit-angle protection device comprising: a first-axis potentiometer comprising first and second magnetic sensing elements and a first magnetic block, with the first and second magnetic sensing elements spaced apart by a first predefined angle centered at a first axis of the driving apparatus, wherein a direction of magnetization of the first magnetic block is perpendicular to the first axis so as for a first-axis sensing signal to be generated in accordance with an output of a variation in a strength of magnetic field induction of the first magnetic block relative to the first-axis potentiometer; a first-axis limit-angle detecting module comprising third and fourth magnetic sensing elements, first and second switch circuits, and three second magnetic blocks, with the second magnetic blocks disposed at positive and negative limit angles and a zero point of the first-axis rotation angle of the driving apparatus, respectively, wherein the third and fourth magnetic sensing elements connected to the first and second switch circuits are disposed at the positive and negative limit angles, respectively, so as to output a plurality of first-axis confirming signals in accordance with magnetic field induction of the second magnetic blocks; and a controller connected to the first-axis potentiometer, the first-axis limit-angle detecting module, and the driving apparatus and adapted to receive the first-axis sensing signal so as to determine a rotation angle about the first axis of the driving apparatus, such that operation of a first-axis driving motor of the driving apparatus stops as soon as the rotation angle about the first axis exceeds a limit angle, wherein the controller receives the first-axis confirming signals, the first-axis driving motor of the driving apparatus stops operating whenever an angle at which one of the first-axis confirming signals is obtained does not equal the rotation angle about the first axis, wherein, from the perspective of the magnetic sensing element-facing sides of the second magnetic blocks, one of the second magnetic blocks which is disposed at the zero point of the rotation angle and the other two second magnetic blocks (224a, 224c) which are disposed at the positive and negative limit-angles of the rotation angle have opposite magnetic poles facing the magnetic sensing elements. a first-axis potentiometer comprising first and second magnetic sensing elements and a first magnetic block, with the first and second magnetic sensing elements spaced apart by a first predefined angle centered at a first axis of the driving apparatus, wherein a direction of magnetization of the first magnetic block is perpendicular to the first axis so as for a first-axis sensing signal to be generated in accordance with an output of a variation in a strength of magnetic field induction of the first magnetic block relative to the first-axis potentiometer; a first-axis limit-angle detecting module comprising third and fourth magnetic sensing elements, first and second switch circuits, and three second magnetic blocks, with the second magnetic blocks disposed at positive and negative limit angles and a zero point of the first-axis rotation angle of the driving apparatus, respectively, wherein the third and fourth magnetic sensing elements connected to the first and second switch circuits are disposed at the positive and negative limit angles, respectively, so as to output a plurality of first-axis confirming signals in accordance with magnetic field induction of the second magnetic blocks; and a controller connected to the first-axis potentiometer, the first-axis limit-angle detecting module, and the driving apparatus and adapted to receive the first-axis sensing signal so as to determine a rotation angle about the first axis of the driving apparatus, such that operation of a first-axis driving motor of the driving apparatus stops as soon as the rotation angle about the first axis exceeds a limit angle, wherein the controller receives the first-axis confirming signals, the first-axis driving motor of the driving apparatus stops operating whenever an angle at which one of the first-axis confirming signals is obtained does not equal the rotation angle about the first axis, wherein, from the perspective of the magnetic sensing element-facing sides of the second magnetic blocks, one of the second magnetic blocks which is disposed at the zero point of the rotation angle and the other two second magnetic blocks (224a, 224c) which are disposed at the positive and negative limit-angles of the rotation angle have opposite magnetic poles facing the magnetic sensing elements.