Abstract: The Auditorium of Tsinghua University, built in 1917, is a major historical and cultural site protected at the national level.Before Tsinghua's centennial anniversary in 2011, the auditorium had been comprehensively reinforced and repaired which aims to make up the defects and deficiencies of the original design and bring overall optimization through reinforcing the structure, replacing deteriorated features, enhancing enjoyment of the performance, adjusting acoustic environment, utilizing the underground space, exhibiting the historical heritage, improving the outdoor environment, etc.Meanwhile, the strengthening and reconstruction work tried to maintain the auditorium's original appearance and make the historical building adapt to modern functions and multiple activities' demands from faculty and students.