A vacuum-molded and reusable limb protecting pad comprising: an airtight bag body made of air impermeable material, wherein a peripheral edge of the airtight bag body is sealed in an airtight manner to form a first containing space; an outer surface of the airtight bag body being provided with an opening at a position corresponding to the first containing space, wherein the opening is in communication with the first containing space; wherein a plurality of locating components are provided between two inner surfaces of the airtight bag body to divide the first containing space into a plurality of locating spaces; a nozzle airtight sealed to the airtight bag body in a position corresponding to the opening and provided with an air channel through which an air extractor is able to pump air out of the first containing space; a plurality of granules filled into the plurality of locating spaces; a filter screen arranged at a position corresponding to the air channel, wherein the sieve size of the filter screen is less than particle size of the granules; and at least one tightening component capable of enabling the limb protecting pad to be wrapped around and abutted against a surface of a limb, so as to adjust tightness of the limb protecting pad around the limb; characterized in that each of the plurality of locating components is formed by a positioning line having a specified length and being provided on two separated inner surfaces of the airtight bag body to divide the first containing space into a plurality of locating spaces which are spaced from but in communication with one another, so that a cross section of the first containing space is always maintained in a predetermined flat narrow shape. an airtight bag body made of air impermeable material, wherein a peripheral edge of the airtight bag body is sealed in an airtight manner to form a first containing space; an outer surface of the airtight bag body being provided with an opening at a position corresponding to the first containing space, wherein the opening is in communication with the first containing space; wherein a plurality of locating components are provided between two inner surfaces of the airtight bag body to divide the first containing space into a plurality of locating spaces; a nozzle airtight sealed to the airtight bag body in a position corresponding to the opening and provided with an air channel through which an air extractor is able to pump air out of the first containing space; a plurality of granules filled into the plurality of locating spaces; a filter screen arranged at a position corresponding to the air channel, wherein the sieve size of the filter screen is less than particle size of the granules; and at least one tightening component capable of enabling the limb protecting pad to be wrapped around and abutted against a surface of a limb, so as to adjust tightness of the limb protecting pad around the limb; characterized in that each of the plurality of locating components is formed by a positioning line having a specified length and being provided on two separated inner surfaces of the airtight bag body to divide the first containing space into a plurality of locating spaces which are spaced from but in communication with one another, so that a cross section of the first containing space is always maintained in a predetermined flat narrow shape.