To provide a process and device for heat-treating steel pipes wherein the steel pipes are induction heated and subsequently water-cooled, which can prevent deterioration of material quality of products caused by temperature unevenness, while retaining productivity at least at a conventional level.

When carrying and heating the entire steel pipe with an induction coil to a temperature within a target range and then water-cooling it, the carrying speed of the steel pipe is set to be equal to or faster than a speed which makes an inner surface temperature of the steel pipe at a given distance apart from the induction coil outlet equal to the midpoint temperature of the target range.