The invention discloses a detecting system comprising a semitrailer, detecting equipment and an auxiliary stand. The detecting equipment can be detachably assembled on the semitrailer through the auxiliary stand, and the semitrailer is a driven trailer with no driving source and comprises a chassis, a support leg arranged on a front lower part of the chassis; and the detecting equipment includes: a radial source of the radiate ray; a vertical support, a horizontal cantilever and a vertical cantilever forming a portal frame; an operation cabin fixedly mounted on the upper part of the auxiliary stand; and a revolution support rotatably mounted on the upper part of the auxiliary stand, wherein the portal frame and the radial source are all mounted on the revolution support so as to rotate with the revolution support, wherein the auxiliary stand is connected to the semitrailer through a standard container interface, thus the detecting system adopts the semitrailer as the chassis.