Comparisons between enhanced and ambient UV-B radiation wheat and millet individuals demonstrate profound effects of enhanced UV-B radiation on plant allometry as well as on the distributions aspects of size by the pot cultivation experiments in greenhouse. The results showed that: ①Enhanced UV-B radiation lead to a significant decrease of plant height and biomass for wheat and millet (P<0.01). Meanwhile, their plant height and biomass frequency distributions under the condition of enhanced UV-B remained positively skewed. ②The Gini coefficient of plant height and biomass were increased notably by enhanced UV-B radiation (P<0.0001).③There were simple allometric relationships between plant height and biomass under enhanced UV-B radiation since these relationships were significantly linear (P<0.05). But the slope of line changed by enhanced UV-B radiation. Consequently, the results implied that the depression effects of UV-B on individuals were not uniform. This allometric analysis may provide a much-needed link between individual plant behaviour to enhanced UV-B radiation and population-level processes.