In establishing a technology system for labor saving in cabbage production, the most important issues are streamlining harvesting, reducing the work load, and reducing the amount of time required. We developed a mechanized trailer-supported harvesting system for cabbage growers in upland field areas. The system will benefit family-managed farms. The system, which requires only three people to operate, consists of a harvester, remote-controlled tractor, and a trailer, where the cabbage can be processed, boxed and palletized. We investigated the suitability of this system from the point of work efficiency, ergonomics, and farm management through trials on a commercial farm. This article presents the results of the field tests of the system.