The utility model relates to a frame-type high pressure gas transporting long tube semi-trailer with six gas cylinders, which belongs to the field of high pressure gas storage and transportation equipment. The frame-type high pressure gas transporting long tube semi-trailer comprises a semi-trailer frame, 720 type large-caliber gas cylinders, a long tube frame, a front support plate, a front end plug, a front safe device, an operation chamber, a rear support plate, a rear end plug, a rear safe device, an air charging and discharging pipeline, a mounting flange, a rupture disk device and an inner pollution discharge device. Wheels and a supporting leg are installed at the lower part of the semi-trailer frame; the long tube frame is positioned at the upper part of the semi-trailer frame; the operation chamber, the rear support plate, the front support plate, the 720 type large-caliber gas cylinders, the air charging and discharging pipeline and the mounting flange are lengthways arranged along the long tube frame; and the three 720 type large-caliber gas cylinders are respectively arranged on an upper layer and a lower layer inside the long tube frame. The frame-type high pressure gas transporting long tube semi-trailer has the advantages of higher volume to weight ratio, less interconnecting pieces, more reasonable pipeline arrangement, lower mass center of the whole semi-trailer and higher driving security and stability.