The invention discloses a high-temperature cable bracket for a diesel engine exhaust collecting pipe and an installation method thereof. The bracket is arranged at the exhaust side of the exhaust collecting pipe and comprises a straight bending bracket and a bending bracket; a plurality of flat plates with more than two waist-shaped holes are welded between two parallel steel pipes of the bracketto form a channel for laying a high-temperature cable; ejecting plates of more than two T-shaped steel plates are vertically welded together with the steel pipes; the straight plates of the T-shaped steel plates are long enough to arrange the channel for laying the high-temperature cable outside a high-temperature isolating layer of the exhaust collecting pipe; and a gap is arranged between the straight bending bracket and the bending bracket. The invention has the advantages of convenience in installation and stable structure and effectively achieves the aims of carrying out mechanical protection on the cable and carrying out high-temperature protection on the cable.