The utility model provides a steel instrument well which comprises a steel well body, a steel well neck and a steel well lid, wherein the steel well neck is connected with an opening in the upper portion of the steel well body, and the steel well lid is arranged on the steel well neck. A steel well bottom is connected below the well walls of the steel well body in a welded mode, the steel well bottom is in seamless connection with the well walls, a support is fixed on the upper side of the steel well bottom, an instrument is contained on the support, pipes are connected to the two ends of the instrument respectively, and the pipes penetrate through the well walls of the steel well body and are in sealing connection with the well walls. The service life of the steel instrument well is guaranteed to be more than 20 years. The environment inside the steel valve well is dry and clean, and therefore the service life of cables, the instrument and the like inside the steel valve well can be prolonged. In the long term, the project investment is reduced, and the steel valve well has the functions, which a traditional instrument well does not have, of saving time, cost, manpower and energy sources and being environmentally friendly and has the overhaul function which can not be achieved in the same-class products.