Photometric data directly obtained in UBVRI or converted to UBVRI magnitudes are tabulated. The data comprise approximately 4600 records from 56 individuals and contains data unpublished at the time of the compilation as well as published data. Introduction: This catalog of globular cluster magnitudes includes both measurements originally obtained on that system and those obtained in other systems which have been converted to the UBVRI system. The equations used for this conversion are given in the source reference. No attempt has been made to put all observations on the same system otherwise. Although both northern and southern UBV data match the original Johnson system, the R and I photometry may differ due to differences in photocells and filters used in defining various sets of standard stars.