Waste water samples were collected from the tanneries of industrial area of Kasur to determine the seasonal variation in chromium resistant bacterial population over a period from January to August, 1999. The pH of the pond water ranged from 7.71 to 9.95, and temperature ranged from 17 degreesC to 35 degreesC from January to August. The chromium content of water samples ranged from 0.05 to 1.6 ppm during these eight months. The minimum inhibitory concentration of Cr6+ was determined for all the bacterial isolates. Some could tolerate as much Cr6+ as 13 mug/ml. After biochemical characterization some of the isolates were identified belonging to the genera Deleya, Melissococcus, Neisseriacinerea, Enterococcus, Bacillus, Kurthia and Listeria. The population of chromium tolerant bacteria fluctuated with the chromium level and the temperature of the water. The most frequently appearing bacterial colonies belonged to the genus Bacillus. They appeared from March to August and had maximum number during August. On the other hand, genus Deleya appeared from January to May and showed maximum number during May. The genera Neisseriacinerea and Melissococcus appeared only in January. Genus Enterococcus appeared in January and February and had higher density in February, while genus Xylella showed up only during February. Genus Kurthia appeared from March to August and showed maximum density in August and genus Listeria appeared from May to August and had maximum density in July.