Abstract: The test methods and contents for a factory building subjected to fire disaster were introduced, includingsection geometry size, concrete strength, steel strength, and carbonation depth in concrete and so on. The firedamaged structure was appraised according to the test results and calculation. The adapted strengthening methodswere put forward through the specific appraisal results. The damaged columns were respectively strengthened withreinforced concrete, externally bonded steel frame and carbon fiber reinforced polymer. For the damaged beams, demolition replacement, strengthened with externally bonded steel frame and carbon fiber reinforced polymer wereused respectively; for the damaged slabs, the demolition replacement, bottom bonded rebar with shotcrete andexternally bonded carbon fiber reinforced polymer were used. The structure completely resumed its bearing capacityafter strengthening.