The invention discloses a telescopic multimeter pen head. The telescopic multimeter pen head comprises a connecting part, a detection head and a connecting line; the connecting part comprises a connecting pipe, long grooves uniformly distributed on the outer wall of the connecting pipe, a thread which is arranged on the outer wall of the connecting pipe and a fastening nut connected with the thread of the connecting pipe; the detection head comprises a detection cylinder, a probe fixed to one end of the detection cylinder, a hole which is formed in the other end of the detection cylinder, a connecting thread A which is arranged on the inner wall of the hole and a connecting thread B which is arranged on the outer wall of the detection cylinder; the connecting line comprises a wire, a connecting head fixed to one end of the wire, a connecting thread C arranged on the outer wall of the connecting head and a protecting layer; the protecting layer comprises a first insulating layer covering the wire, a stainless steel wire net covering the first insulating layer, a second insulating layer covering the stainless steel wire net and an outer protecting layer covering the second insulatinglayer.