The invention relates to a box type steel tube guardrail device. The device includes a box type steel tube guardrail and a plurality of guardrail brackets; each guardrail bracket includes an fixed endand a supporting end which are integrally formed, one end of the fixed end is fixed on the bottom of a main rail, and the other end of the fixed end is connected with the bottom of the supporting end; the supporting end is fixedly connected with the box type steel tube guardrail; the top of the box type steel tube guardrail is higher than the main rail, and the box type steel tube guardrail includes a straight section and cushion sections located at the two ends of the straight section; the straight section is parallel with the extending direction of the main rail, and each cushion section includes a first bending part and a second bending part. Moreover, the invention relates to the installation method of the box type steel tube guardrail device. The box type steel tube guardrail is usedfor replacing traditional steel (trough type) and UIC33 trough type guardrail, and the resistance to lateral force is obviously improved. The box type steel tube guardrail device has the advantages that the structure is simple, materials are convenient to obtain, the strength is high, and processing and maintenance are convenient.