Measurements of solar ultraviolet-B (UV-B) in the range (280-315 nm) and total global solar irradiation (G) for the period 2002-2006 in a continental Mediterranean environment have been analyzed. UV-B and G data have been recorded at the Low Atmosphere Research Laboratory, Valladolid, Spain, using a YES UVB-1 pyranometer and a Kipp&Zonen CM-6 radiometer, respectively. According to the cloud conditions, the time data series shows that the highest UV-B values are obtained in June and the lowest ones are obtained in December. A comparison of monthly UV-B values reveals that some summer months show more dispersion than winter ones. An empirical relationship between UV-B and G was established to estimate the daily UV-B irradiation from commonly measured daily total global solar irradiation. The annual cycle effects of the solar zenith angle and the ozone total column have been taken into account. A correction factor that depends on the daily total ozone column has been included in the relationship between UV-B and total global solar irradiation. The performance of this relationship has been evaluated comparing estimated and measured UV-B values in three different stations. Scatterplot, root-mean-square error (RMSE), mean bias error (MBE), and linear regression correlation coefficient have been used to compare measured and estimated values. The results of this comparison show that the correlation coefficients were similar to 1 while the RMSE ranges between 2.10 kJ m-2 and 1.94 k Jm-2 and, in percentage, 9.18% and 7.64%, respectively. According to these results, it can be concluded that total global solar irradiation is an appropriate variable to obtain UV-B daily values in places where ultraviolet radiation is not measured or to extend the existing data set back in time.