The present invention provides a telescopic magnetic-absorption base capable of disassembling and assembling in a sleeve quickly. The magnetic-absorption base comprises: a magnetic-absorption device,wherein the magnetic-absorption device comprises a first end and a second end, and the first end of the magnetic-absorption device has magnetism; and a detachable positioning device, wherein the detachable positioning device is provided with a connecting end, the connecting end of the detachable positioning device is slidably arranged at the second end of the magnetic-absorption device, and thus the magnetic-absorption device can produce axial sliding motion relative to the detachable positioning device. The end, opposite to the connecting end, of the detachable positioning device is providedwith an elastic quick disassembling device. The elastic quick disassembling device allows the detachable positioning device to be assembled in the sleeve, wherein the detachable positioning device canbe disassembled from the sleeve quickly. When the sleeve is damaged, the telescopic magnetic-absorption base can be quickly disassembled from the sleeve, and then the magnetic-absorption base can beassembled into another new sleeve.