Tong-Il Han has performed with many of the finest orchestras around the world such as the New York Philharmonic, Chicago Symphony, Los Angeles Philharmonic, Cleveland Orchestra, Detroit Symphony, London Philharmonic, Royal Philharmonic, Scottish National Orchestra, Oslo Philharmonic, Monte Carlo Orchestra, Rotterdam Philharmonic, Polish Radio National Orchestra, Budapest Radio Symphony Orchestra, and Russian National Symphony, among many others. The conductors with whom he has collaborated include Bernard Haitink, Herbert Blomstedt, Edo de Waart, Raphael Fruhbeck de Burgos, Charles Dutoit, Lukas Foss, Eugene Jochum, Raymond Leppard, Robert Shaw, Stanislaw Skrowaczeski, and David Zinman. The government of Republic of Korea has conferred on him the Order of Moran (Peony), the highest civil service award.

Tong-Il Han's many records include Chopin's Twenty-Four Preludes, Four Ballades and Four Scherzos, eight Sonatas by Beethoven (including the last five), Sonatas by Schubert and Brahms, and a group of shorter piano works under the title "Music I Love To Play". He also has recorded Sonatas for Cello and Piano by Brahms, and Schumann's Fantasy Pieces with cellist Leslie Parnas. The CD titled "The Kennedy White House Concert" (the live concert given at the White House) has been released. In this concert recording Han performed Debussy's "Reflet dans l'eau" and Liszt's "Mephisto Waltz". His latest CD released in June 2004 was recorded in Rome . This includes major works by Schumann, Beethoven, and Brahms.

On June 1, 2004 , to celebrate the fiftieth anniversary of his departure from Korea as a young boy, Han performed the same program that he witnessed at a Lewison Stadium concert given by the New York Philharmonic Orchestra upon arrival in New York City in 1954: Beethoven's "Egmont" Overture, Piano Concerto No. 4, and Piano Concerto No. 5 ("Emperor"). The Seoul Philharmonic Orchestra, under the direction of Han's childhood friend, Dae-Uck Lee, accompanied the concertos at Seoul Performing Arts Center. The evening's highlight was the participation of his ninety-one year old father, playing timpani for the Beethoven "Emperor" Piano Concerto.

As Artistic Director of the Tong-Il Han Piano Institute, he has held summer piano festivals in London, Budapest, Boston, Honolulu, Vancouver, Pebble Beach, Hiroshima, Seoul, and Courchevel, among other places. The 2008 Piano Festival will be held at Brigham Young University in Hawaii.

Tong-Il Han has taught at Indiana University, Illinois State University, University of North Texas, and Boston University. From 2005-2007 Tong-Il Han served as Dean of the College of Music at University of Ulsan, Republic of Korea, and continues there as Chair Professor of Music. Guest Professor positions include those at Elisabeth University of Music in Hiroshima, Japan and Suncheon University, Korea. In Seoul, Korea Professor Tong-Il Han mentors a highly accomplished group of young pianists enrolled in the Tong-Il Han Piano Academy. These young artists range in age from middle school through university. Tong-Il Han has extended his musical creativity to Thailand as Artistic Director of the Chiang Mai Music Festival now enjoying its third year.

As both concert artist and teacher Tong-Il Han draws deeply on his Korean roots and Western musical heritage. For many years his foremost commitment has been to engender the artistic and humanistic development of the next generation of artists, teachers, and audiences in both his native Orient and in the West.