The utility model relates to an arrangement structure with the diameter of 5.5 meters of an illumination lamp in a cable tunnel. The arrangement structure comprises a plurality of LED lamps which are divided into two rows to be arranged on the two sides of the top of the tunnel, the two rows of LED lamps are arranged in a staggered mode, and the interval between adjacent LED lamps in the same row is 7-8 meters. Compared with the prior art, the arrangement structure with the diameter of 5.5 meters of the illumination lamp in the cable tunnel has the advantages of being convenient to use, saving in energy and the like.