The paper presents the nature of long-term seasonal and yearly variations of tropospheric and stratospheric ozone over Thumba (8.5°N, 77°E) and Bangalore (13°N, 77.5°E), India. Seasonal variations clearly reveal that stratospheric ozone concentration attained comparatively higher value in the months from July to September while lower tropospheric ozone concentration at the same time over the above stations during the period 1979-2005. Yearly variation shows increasing trend in tropospheric ozone but decreasing trend in stratospheric ozone from 1979 to 2005. Undesirable environmental effects due to such tropospheric rise and stratospheric decline in ozone are also mentioned. © 2012 IACS.