Photometric data from the All-Sky Automatic Survey (ASAS) - South (Declination less than 29 degrees) Survey have been used for the identification of bright stars located near the sources from the ROSAT All Sky Survey Bright Source Catalog (RASSBSC). In total, 6,028 stars brighter than 12.5 magnitude in the I- or the V-bands have been selected and analyzed for periodicity. Altogether, 2,302 variable stars have been found with periods ranging from 0.137 days to 193 days. Most of these stars have X-ray emission of coronal origin, but there are a few cataclysmic binaries and early type stars with colliding winds. Whenever it was possible, the authors collected data available in the literature so as to verify the periods and to classify variable objects. The catalog includes 1,936 stars (1,233 new) considered to be variable due to presence of spots (rotationally variable), 127 detached eclipsing binary stars (33 new), 124 contact binaries (11 new), 96 eclipsing stars with deformed components (19 new), 13 ellipsoidal variables (4 new), 5 miscellaneous variables and one pulsating RR Lyr type star (blended with an eclipsing binary). More than 70% of the new variable stars have amplitudes smaller than 0.1 magnitudes, but for the star ASAS 063656-0521.0 the authors have found the largest known amplitude of brightness variations due to the presence of spots (up to Delta V = 0.8 magnitudes). This table was created by the HEASARC in May 2018, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AcA/62/67">CDS Catalog J/AcA/62/67</a> files catalog.dat and remarks.dat. This is a service provided by NASA HEASARC .