To provide a cord-like heater assembly that is a simple structure and that is improved in assembling workability.

The cord-like heater assembly 10 consists of a cord-like heater 1, a cylindrical protective tool 2, a lock tool 3, and a stopper tool 4 capable of mounting the lock tool 3. The cord-like heater 1 is in a state of being folded back, the protective tool 2 is arranged at the folded part of the cord-like heater 1 covered in the same 1, the lock tool 3 is fitted to the protective tool 2, and the stopper tool 4 is arranged so as to be fixed to the both the folded parts of the cord-like heater 1. The cord-like heater 1 has a heater wire part and a lead wire part formed in series. The stopper tool 4 is arranged so as to be positioned at a connecting part of the heater wire part and the lead wire part of the cord-like heater 1.