The Asiago Catalog of 2004 Quasi Stellar Objects (QSOs) is an updated version of that published by Barbieri, Capaccioli and Zambon in 1975 (1975MmSAI..46..461B). Most of the information of these objects are taken from the literature published before Dec. 31, 1981. Specifically, the catalog.dat file contains names, equatorial and galactic coordinates, photometry, redshifts, information on radio emission, variability, morphology, presence of absorption lines, for 2004 QSOs. The indexed references (in refs.dat) and further detailed information (in remarks.dat) concerning absorption spectra, X-ray properties, and cross-reference tables are also provided.