To provide a tape-like electric heater for heating a pipe which allows installation work to be performed easily and attractively, and which can decrease heat radiation.

The electric heater 10 is partitioned in the width direction to provide a heating zone 60 including a heater wire 30, and a non-heating zone 70 not including the heater wire 30. The non-heating zone 70 is made cuttable. The heating zone 60 includes connectors at both longitudinal ends, and two or more heating zones can be combined with each other. A single power supply, including 100 V and 200 V power supplies, can be used for all of the connected electric heaters 10.