Using synchrotron radiation as a continuum background, the cross sections of SO2 in the 208--228 and 299--340 nm region and of CS2 in the 318--350 nm region have been measured with a bandwidth of 0.06 nm. It has been confirmed that the reported band positions of SO2 in the 170--315 nm region by Warneck et al. (J. Chem. Phys. 40, 1132, 1964) should all be shifted by ~0.3 nm toward shorter wavelengths. An important application of the present results is found in the SO2 and CS2 mixing ratio calculations for Venus and Io.