[Objective] The aim of this study was to investigate the content changes and their correlations of the photosynthetic pigment,phenols,including total phenols,total flavonoids and anthocyanins,and total saponins of the one-year-old P.notoginseng plants under supplemental UV-B stress in fields.[Method] The one-year-old plants were irradiated by UV-B in field for 1 min per day,and the plants under the UV-B lamp were regarded as a circle center,achieving an annular leaf-sampling.The photosynthetic pigment,phenols and total saponins of the leaves were determined spectrophotometrically.[Result] With the increase of sampling radius,the supplemental UV-B intensity decreased significantly,the contents of chlorophyll (Chl) a,Chl b,Chl (a+b),carotenoid (Car) and total photosynthetic pigment (Chl+Car) of the leaves increased extremely significantly,the Chl a/b and total phenol content (TPC) decreased extremely significantly,but the Chl (a+b)/Car changes were not significant.The contents of total flavonoids,anthocyanins and saponins all increased due to the increasing of UV-B,displaying dose effects.The UV-B intensity was positively correlated with the Chl a/b,and negatively with the Chl a,Chl b,Chl (a+ b),Car and (Chl+Car) contents; and the two of TPC,total flavonoid content (TFC),total anthocyanin content (TAC) and total saponin content (TSC) were positively correlated,all reaching extremely significant level.The UV-B intensity was positively and significantly correlated with the total flavonoid content (TFC),negatively and significantly with the Chl (a+b)/Car,and positively and insignificantly with the TPC,TAC and TSC.[Conclusion] For one-year-old plants of P.notoginseng,UV-B can decrease the contents of the Chl a,Chl b,Chl (a+b),Car and (Chl+Car) and increase the Chl a/b and TPC,and,furthermore,induce the increases of the TFC,TAC and TSC in a dose-dependent manner.However,UV-B can hardly change the Chl (a+b)/Car.The supplemental UV-B of well